Process for olefin polymerisation using group 4 metallocene as catalysts

ABSTRACT

A process for the preparation of a random propylene copolymer comprising polymerising propylene and at least one C2-10 alpha olefin (especially ethylene) in the presence of a catalyst; wherein said catalyst comprises: (i) a complex of formula (I): wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R′ 2 C—, —R′ 2 C—CR′ 2 —, —R′ 2 Si—, —R′ 2 Si—SiR 2 —, —R′ 2 Ge—, wherein each R′ is independently a hydrogen atom, C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl; each R 1  is a C4-C20 hydrocarbyl radical branched at the β-atom to the cyclopentadienyl ring, optionally containing one or more heteroatoms belonging to groups 14-16, or is a C3-C20 hydrocarbyl radical branched at the β-atom to the cyclopentadienyl ring where the β-atom is an Si-atom; n is 0-3; each R 18  is the same or different and may be a C1-C20 hydrocarbyl radical optionally containing one or more heteroatoms belonging to groups 14-16; each R 4  is a hydrogen atom or a C1-6-hydrocarbyl radical; each W is a 5 or 6 membered aryl or heteroaryl ring wherein each atom of said ring is optionally substituted with an R 5  group; each R 5  is the same or different and is a C1-C20 hydrocarbyl radical optionally containing one or more heteroatoms belonging to groups 14-16; and optionally two adjacent R 5  groups taken together can form a further mono or multicyclic ring condensed to W optionally substituted by one or two groups R 5 ; and (ii) a cocatalyst comprising an organometallic compound of a Group 13 metal.

This invention relates to catalysts comprising bridged bis indenylΠ-ligands useful in the formation of olefin polymerisation catalysts, aswell as the use thereof in olefin polymerisation, in particular forpolymerising propylene and especially propylene copolymers withethylene. In particular, the invention relates to catalysts whichcomprise certain bridged bis indenyl complexes in solid form. e.g.supported or ideally in solid but unsupported form. Certain complexes ofthe invention are also new and form still yet further aspects of theinvention as do certain processes for their manufacture.

Metallocene catalysts have been used to manufacture polyolefins for manyyears. Countless academic and patent publications describe the use ofthese catalysts in olefin polymerisation. Metallocenes are now usedindustrially and polyethylenes and polypropylenes in particular areoften produced using cyclopentadienyl based catalyst systems withdifferent substitution patterns.

These metallocenes can be used in solution polymerisation but results ofsuch polymerisations have generally been poor. These metallocenes aretherefore conventional supported on a carrier such as silica. Researchhas found that heterogeneous catalysis (in which the catalyst particlesdo not dissolve in the reaction medium) gives rise to better polymerproducts than homogeneous catalysis (in solution). The use therefore ofa support is common place. Despite several years of development of thiscatalyst technology, there is still room for improved activity, andimproved polymer particle formation.

In WO03/051934, the inventors proposed an alternative form of catalystwhich is provided in solid form but does not require a conventionalexternal carrier material such as silica. The invention is based on thefinding that a homogeneous catalyst system containing an organometalliccompound of a transition metal can be converted, in a controlled way, tosolid, uniform catalyst particles by first forming a liquid/liquidemulsion system, which comprises as the dispersed phase, said solutionof the homogeneous catalyst system, and as the continuous phase asolvent immiscible therewith, and then solidifying said disperseddroplets to form solid particles comprising the said catalyst.

The invention described in WO03/051934 enabled the formation of solidspherical catalyst particles of said organotransition metal catalystwithout using e.g. external porous carrier particles, such as silica,normally required in the art. Thus, problems relating to catalyst silicaresidues can be solved by this type of catalyst. Further, it could beseen that catalyst particles having improved morphology, will give, dueto the replica effect, polymer particles having improved morphology aswell.

Although a lot of work has been done in the field of metallocenecatalysts, both with conventional supported catalysts as well with solidcatalysts prepared according to the principles as described in saidWO03/051934, there still remain some problems, which relate especiallyto the productivity or activity of the catalysts. The productivity oractivity has been found to be relatively low, especially when polymersof low melt index (MI) (i.e. high molecular weight, M_(w)) are producedusing known catalysts.

There remains a need therefore to find new catalysts for olefinpolymerisation, which are able to produce polymers with desiredproperties and which have high activity and/or productivity. Further, itis highly desired in many polymer applications that inorganic residues,e.g. silica residues, in the final product are reduced as much aspossible.

A further problem relating to the catalyst activity seems to be thatactivity of known catalysts is not at a sufficiently high level over abroad range of hydrogen concentration, i.e. where the skilled man isproducing lower or higher Mw polymers. Thus, catalysts having broaderoperating windows, i.e. good activity over a broad range of molecularweights of the polymer, are highly desired. Further, the problems withconventional silica supported catalysts, i.e. low productivity, have tobe avoided. Producing polymers with high isotacticity and hence highercrystallinity and thermal resistance is also desirable.

In particular, the present inventors were faced with the problem ofmanufacturing a polymer with high molecular weight (i.e. enabling theformation of polymer components with low melt index). This had to beachieved whilst maintaining high catalyst activity and productivity.

As a consequence, the inventors set out to develop a catalyst having asuperior polymerisation behaviour than the above mentionedpolymerisation catalyst systems regarding one or more of the followingcharacteristics:

-   -   improved performance towards high molecular weight propylene        copolymers    -   improved productivity in producing propylene copolymers    -   obtaining propylene copolymers with low xylene solubles even in        the presence of relatively high amount of comonomer.

The present inventors have now found a new class of olefinpolymerisation catalysts, which are able to solve the problems disclosedabove, and which catalysts are not previously described in the art. Theinvention combines known supporting techniques, for example using silicaas described in WO2006/097497, or the catalyst emulsion/solidificationtechniques of WO03/051934 with a specific group of metallocene complexesbased on a bis-indenyl structure in which the indenyl group carries afive-membered ring (thus forming a trihydroindacenyl ligand). Also, the2-position of the indenyl ring must carry a group, branched at the βcarbon to the cyclopentadienyl ring. This combination surprisinglyresults in catalysts having high activity, e.g. improved activity overthe known catalysts prepared according to WO03/051934. Moreover, thefeatures of the catalyst of the invention enable the formation ofpolymers having a broad range of molecular weights, especially, veryhigh molecular weight products. Further, as a special embodiment, theinvention further provides a catalyst, where no silica support materialneed be used. This avoids any problems relating to the use of theconventional supported catalysts, such as silica supported catalysts.

These polymers operate well over a broad range of hydrogen pressures,and form advantageous polymers.

The inventors have also found that the new catalyst described herein isideal for the production of random propylene/ethylene copolymers withincreased molecular weight. This can be achieved with high productivityand high catalyst activity. The presence of ethylene surprisinglyenhances catalyst activity. Moreover, and surprisingly, thepropylene-rich copolymers formed using the catalyst of the presentinvention exhibit decreasing melt index with increasing ethyleneconcentration. Furthermore, the xylene soluble content of the polymersremains low indicating even comonomer distribution.

Complexes similar to those used in the manufacture of the catalysts ofthe invention are disclosed in the prior art but they do not show thesame advantageous combination of improved properties. Moreover, theimportance of the branch at the β-position of the substituent on the2-position of the indenyl ligand is not appreciated. Moreover, thecomplexes of the invention generally represent a selection from the verybroad disclosures of metallocene catalysts in the prior art.

In WO2006/097497 some broadly defined metallocene complexes aredisclosed based on bis indenyl structures in which a non aromatic ringis bound to the 6-membered ring of the indenyl group. Some compoundswith a 5-membered ring attached to the indenyl ring (e.g. those offormula II of WO2006/097497) are disclosed but these metallocenes do notshow all required properties. Moreover, the importance of a branchedgroup at the β-position of the substituent on the 2-position of theindenyl ligand is not appreciated.

WO2005/058916 primarily describes asymmetric metallocenes in which the2-position substituents are different.

WO2009/054832 discloses conventionally supported metallocene catalystswhich are branched at the 2-position of the cyclopentadienyl ring in atleast one of the ligands making up the catalyst. The exemplified speciesare however, bis-indenyl catalysts.

It has now surprisingly been found that using the particular complexesdescribed below in solid form the resulting catalysts comprehensivelyoutperform known catalysts prepared according to the method ofWO03/051934. Moreover, these catalysts outperform the preferredmetallocenes of WO2006/097497 even when these are formulated using thetechniques of WO03/051934. This is an entirely surprising result.

Thus, viewed from one aspect the invention provides a catalystcomprising:

(i) a complex of formula (I):

wherein

M is zirconium or hafnium;

each X is a sigma ligand;

L is a divalent bridge selected from —R′₂C—, —R′₂C—CR′₂—, —R′₂Si—,—R′₂Si—SiR′₂—, —R′₂Ge—, wherein each R′ is independently a hydrogenatom, C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl,C7-C20-arylalkyl or C7-C20-alkylaryl;

each R¹ is a C4-C20 hydrocarbyl radical branched at the β-atom to thecyclopentadienyl ring, optionally containing one or more heteroatomsbelonging to groups 14-16, or is a C3-C20 hydrocarbyl radical branchedat the β-atom to the cyclopentadienyl ring where the β-atom is anSi-atom;

n is 0-3;

each R¹⁸ is the same or different and may be a C1-C20 hydrocarbylradical optionally containing one or more heteroatoms belonging togroups 14-16;

each R⁴ is a hydrogen atom or a C₁₋₆-hydrocarbyl radical;

each W is a 5 or 6 membered aryl or heteroaryl ring wherein each atom ofsaid ring is optionally substituted with an R⁵ group;

each R⁵ is the same or different and is a C1-C20 hydrocarbyl radicaloptionally containing one or more heteroatoms belonging to groups 14-16;and optionally two adjacent R⁵ groups taken together can form a furthermono or multicyclic ring condensed to W optionally substituted by one ortwo groups R⁵;

and (ii) a cocatalyst comprising an organometallic compound of a Group13 metal.

The catalyst of the invention is in solid particulate form eithersupported on an external carrier material, like silica or alumina, or,in a particularly preferred embodiment, is free from an externalcarrier. Ideally, the catalyst is obtainable by a process in which

(a) a liquid/liquid emulsion system is formed, said liquid/liquidemulsion system comprising a solution of the catalyst components (i) and(ii) dispersed in a solvent so as to form dispersed droplets; and

(b) solid particles are formed by solidifying said dispersed droplets.

Viewed from another aspect the invention provides a process for themanufacture of a catalyst as hereinbefore defined comprising obtaining acomplex of formula (I) and a cocatalyst as hereinbefore described;

forming a liquid/liquid emulsion system, which comprises a solution ofcatalyst components (i) and (ii) dispersed in a solvent, and solidifyingsaid dispersed droplets to form solid particles.

Viewed from another aspect the invention provides the use in olefinpolymerisation of a catalyst as hereinbefore defined, especially for theformation of an random copolymer, especially of ethylene and propylene.

Viewed from another aspect the invention provides a process for thepolymerisation of at least one olefin comprising reacting said at leastone olefin with a catalyst as hereinbefore described, especially for theformation of a random propylene copolymer, in particular a randompropylene/ethylene copolymer comprising polymerising propylene and atleast one C2-10 alpha olefin (especially ethylene) in the presence ofsaid catalyst.

DEFINITIONS

Throughout the description the following definitions are employed.

By free from an external carrier is meant that the catalyst does notcontain an external support, such as an inorganic support, for example,silica or alumina, or an organic polymeric support material.

For nomenclature purposes, the following numbering scheme will be usedfor the trihydro-s-indacenyl backbone of the bridged ligand. L is adivalent bridge and has the same definition as described above. Itshould be noted that trihydro-s-indacenyl can be considered as5,6-trimethyleneindenyl.

The term C₁₋₂₀ hydrocarbyl group therefore includes C₁₋₂₀ alkyl, C₂₋₂₀alkenyl, C₂₋₂₀ alkynyl, C₃₋₂₀ cycloalkyl, C₃₋₂₀ cycloalkenyl, C₆₋₂₀ arylgroups, C₇₋₂₀ alkylaryl groups or C₇₋₂₀ arylalkyl groups or of coursemixtures of these groups such as cycloalkyl substituted by alkyl.

Unless otherwise stated, preferred C₁₋₂₀ hydrocarbyl groups are C₁₋₂₀alkyl, C₄₋₂₀ cycloalkyl, C₅₋₂₀ cycloalkyl-alkyl groups, C₇₋₂₀ alkylarylgroups, C₇₋₂₀ arylalkyl groups or C₆₋₂₀ aryl groups, especially C₁₋₁₀alkyl groups, C₆₋₁₀ aryl groups, or C₇₋₁₂ arylalkyl groups, e.g. C₁₋₈alkyl groups. Most especially preferred hydrocarbyl groups are methyl,ethyl, propyl, isopropyl, tertbutyl, isobutyl, C₅₋₆-cycloalkyl,cyclohexylmethyl, phenyl or benzyl.

The term halo includes fluoro, chloro, bromo and iodo groups, especiallychloro groups, when relating to the complex definition.

The term heterocyclic group means a preferably monocyclic non aromaticring structure comprising at least one heteroatom, e.g. piperidinyl orpiperazinyl.

The term heteroaryl means a preferably monocyclic aromatic ringstructure comprising at least one heteroatom. Preferred heteroarylgroups have 1 to 4 heteroatoms selected from O, S and N. Preferredheteroaryl groups include furanyl, thiophenyl, oxazole, thiazole,isothiazole, isooxazole, triazole and pyridyl.

Any group including “one or more heteroatoms belonging to groups 14-16”preferably means O, S or N. N groups may present as —NH— or —NR″— whereR″ is C1-10 alkyl. There may, for example, be 1 to 4 heteroatoms.

The oxidation state of the metal ion is governed primarily by the natureof the metal ion in question and the stability of the individualoxidation states of each metal ion.

It will be appreciated that in the complexes of the invention, the metalion M is coordinated by ligands X so as to satisfy the valency of themetal ion and to fill its available coordination sites. The nature ofthese σ-ligands can vary greatly.

Catalyst activity is defined in this application to be the amount ofpolymer produced/g catalyst/h. Catalyst metal activity is defined hereto be the amount of polymer produced/g Metal/h. The term productivity isalso sometimes used to indicate the catalyst activity although herein itdesignates the amount of polymer produced per unit weight of catalyst.

DETAILED DESCRIPTION OF INVENTION

The complexes and hence catalysts of the invention are based on formula(I) as hereinbefore defined which, inter alia, combines the use of thetrihydroindacenyl tricyclic ring structure with a substituent at the2-position that is branched β to the cyclopentadienyl ring.

The two multicyclic ligands making up the complex of formula (I) arepreferably identical and hence the complex of formula (I) may besymmetrical. The complexes of the invention may be in their meso orracemic forms (or a mixture thereof). Preferably, the racemic (rac) formis used.

M is preferably Zr or Hf, especially Zr.

Each X, which may be the same or different, is preferably a hydrogenatom, a halogen atom, a R, OR, OSO₂CF₃, OCOR, SR, NR₂ or PR₂ groupwherein R is a linear or branched, cyclic or acyclic, C1-C20-alkyl,C2-C20 alkenyl, C2-C20 alkynyl, C6-C20-aryl, C7-C20-alkylaryl orC7-C20-arylalkyl radical; optionally containing heteroatoms belonging togroups 14-16. R is preferably a C₁₋₆ alkyl, phenyl or benzyl group.

Most preferably each X is independently a hydrogen atom, a halogen atom,C₁₋₆-alkoxy group or an R group, e.g. preferably a C₁₋₆-alkyl, phenyl orbenzyl group. Most preferably X is chlorine or a methyl radical.Preferably both X groups are the same.

L is preferably a bridge comprising a heteroatom, such as silicon or,germanium, e.g. —SiR⁶ ₂—, wherein each R⁶ is independently C1-C20-alkyl,C6-C20-aryl or tri(C1-C20-alkyl)silyl-residue, such as trimethylsilyl.More preferably R⁶ is C₁₋₆-alkyl, especially methyl. Most preferably, Lis a dimethylsilyl or diethyl bridge.

R¹ is branched β to the cyclopentadienyl ring. By branched β to thecyclopentadienyl ring is meant that the second atom from thecyclopentadienyl ring must be secondary or tertiary, preferablysecondary. This atom is preferably Si or C but is most preferably C. TheR¹ radical preferably comprises at least 4 carbon atoms in the chain, oralternatively at least 6 carbon atoms. Where an Si atom is present β tothe cyclopentadienyl ring it is possible for there to be three carbonatoms present in the R¹ group in addition to the Si atom at the betaposition.

It will also be appreciated that where a cyclic group such as acycloalkyl group, heterocyclic, heteroaryl or aryl group is present atthe atom 0 to the cyclopentadienyl then there is a branch present.

The R¹ group may contain one or more heteroatoms belonging to groups14-16, e.g. O, N or S. There may be 1 to 3 of such heteroatoms. Theseheteroatoms may be positioned to allow formation of a heterocyclic orheteroaryl group in the R¹ group e.g. a CH₂-heteroaryl orCH₂-heterocyclic group having 3-10 carbon atoms and one to threeheteroatoms.

It is preferred that heteroatoms in the R¹ group (other than Si at thebeta position as discussed below) are not positioned at the atoms α, β,or γ to the cyclopentadienyl ring. Thus, the backbone atom positioned αto the ring is preferably C, the backbone atom β to the ring is C or Siand the atoms attached to β position (other than hydrogen) are C atoms.Heteroatoms, if present should be positioned at least delta to thecyclopentadienyl ring. Preferably there are no heteroatoms present ingroups R¹.

Where there is an Si atom β to the cyclopentadienyl ring it is preferredif there are no other heteroatoms present in the R¹ group. Where Siinterrupts the carbon chain β to the cyclopentadienyl ring, preferredsuch groups include CH₂—SiR¹⁰ ₃ where R¹⁰ is a C₁₋₆ alkyl group, e.g.methyl.

Preferably R¹ is a C4-20 hydrocarbyl group, more preferably C4-C12hydrocarbyl branched to the cyclopentadienyl ring, optionally containingone or more heteroatoms belonging to groups 14-16.

Radical R¹ is preferably a suitably branched C4-C20-alkyl, aCH₂-cycloalkyl group having 4 to 12 carbon atoms or a CH₂-aryl radicalcontaining from 7 to 11 carbon atoms.

In a preferred embodiment, R¹ is the group —CH₂—R^(1′), i.e. the link tothe cyclopentadienyl ring is via a methylene group and R^(1′) representsthe remainder of the R¹ group, e.g. a C3-19 hydrocarbyl group optionallycontaining one or more heteroatoms belonging to groups 14-16 or a C2-19hydrocarbyl group where the atom to the cyclopentadienyl ring is Si.

In particular, R¹ represents a C₃₋₇-cycloalkyl group (optionallysubstituted by C₁₋₆-alkyl), a C₆₋₁₀-aryl group, especially phenyl or anC₃₋₈-alkyl group (such that the beta position to the cyclopentadienyl isbranched). In some embodiments the R^(1′) group can represent aheteroaryl or heterocyclic group having 2 to 8 carbon atoms and one tothree heteroatoms (e.g. S, N or O). Heteroatoms, if present, shouldpreferably be positioned at least delta to the cyclopentadienyl ring.

Suitable heteroaryl groups include pyrrolyl, indolyl, furanyl, oxazole,thiazole, isothiazole, isooxazole, triazole and pyridyl. Suitableheterocyclic groups include piperidinyl and piperazinyl.

In a further preferred embodiment therefore, R₁ is a groupCH₂—C(R₃)_(3-q)(H)_(q) wherein each R₃ is a C₁₋₆-alkyl group or togethertwo R₃ groups form a C₃₋₇-cycloalkyl ring. The subscript q can be 1 or0.

More preferably R¹ is a suitably branched C₄₋₁₀-alkyl radical,preferably a suitably branched C₄₋₈-alkyl radical. R¹ is ideally anisobutyl or —CH₂CH(Me)(Et) group. Alternatively, R¹ is —CH₂C₆H₁₁ whereC₆H₁₁ is cyclohexyl, CH₂C₆H₁₁(Me) where the cyclohexyl is substituted bymethyl or —CH₂C₆H₅ (benzyl).

If substituted by a group R¹⁸, it is preferred if there are 1 to 3,preferably 1 or 2 such groups present. The 5-membered non aromatic ringis however, preferably unsubstituted (i.e. n is zero).

Preferably R¹⁸ is linear or branched, cyclic or acyclic, C1-20-alkyl,C2-C20 alkenyl, C2-C20 alkynyl, C6-C20-aryl, C7-C20-alkylaryl orC7-C20-arylalkyl radical, optionally containing one or more heteroatomsbelonging to groups 14-16.

In some embodiments of the invention R¹⁸ may represent a heteroarylgroup, i.e. where a heteroatom or heteroatoms from groups 14-16 ispresent. Suitable heteroaryl groups include pyrrolyl, indolyl, furanyl,thiophenyl, oxazole, thiazole, isothiazole, isooxazole, triazole andpyridyl. It is preferred however if R¹⁸ is free of heteroatoms.

More preferably R¹⁸ is a linear or branched, C₁₋₁₀-alkyl radical. Morepreferably R¹⁸ is a methyl or ethyl radical. It is within the scope ofthe invention for two R¹⁸ groups to bind to the same atom of the ringalthough this is not preferred. Preferably the ring is unsubstituted,i.e. n is zero.

R⁴ is preferably a hydrogen atom or C₁₋₆ alkyl such as methyl, ethyl,propyl or isopropyl group, most preferably methyl or especiallyhydrogen.

W is preferably an optionally substituted phenyl group, or a 5 or 6membered heteroaryl group such as a furanyl, thiophenyl, pyrrolyl,triazolyl, and pyridyl.

Any five membered heteroaryl group should preferably comprise oneheteroatom in the ring, such as O, N or S.

Preferably W is a phenyl derivative. More preferably the phenylderivative is unsubstituted or carries one substituent.

The optional substituent on any W group is R⁵. If present, there shouldbe 1 or 2 R⁵ groups, preferably one R⁵ group.

Preferably R⁵ is a linear or branched, cyclic or acyclic, C1-C20-alkyl,C2-C20 alkenyl, C2-C20 alkynyl, C6-C20-aryl, C7-C20-alkylaryl orC7-C20-arylalkyl radical optionally containing one or more heteroatomsbelonging to groups 14-16. Preferably R⁵ is a linear or branched, cyclicor acyclic, C1-C10-alkyl group. Most preferably R⁵ is a tert-butylgroup.

It is preferred that any R⁵ group present is located para to the bond tothe indenyl group, i.e. at the 4-position of the ring.

In one preferred embodiment two adjacent R⁵ groups taken together canform a further mono or multicyclic ring condensed to W. The new ring ispreferably 5 or 6 membered or the R⁵ groups preferably form two newrings such as one further five membered and six membered ring.

The new ring or rings can be aliphatic or aromatic. Preferably any newring forms an aromatic system with the W ring to which it is attached.

In this way groups such as indolyl, carbazolyl, benzothiophenyl andnaphthyl can be formed at position W. It is also within the scope of theinvention for these new rings to be substituted by 1 or 2 R⁵ groups (inwhich the option of two adjacent R₅ groups forming another ring isexcluded).

In a most preferred embodiment, W is a phenyl group carrying one R⁵substituent. Preferably that substituent is carried para to the bond tothe indenyl ring. That substituent is also preferably a C₁₋₁₀-alkylradical. Furthermore, the carbon atom of the R⁵ group bonding to the Wring is preferably a tertiary carbon atom.

Thus viewed from another aspect the invention provides a complex offormula (II):

wherein

M is Zr or Hf;

each R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) wherein R³ is a C₁₋₆-alkylgroup or together two R³ groups form a C₃₋₇-cycloalkyl ring wherein saidring is optionally substituted by a C₁₋₆ alkyl group and q can be 1 or0;

L is ethylene or SiR⁶ ₂;

R⁶ is C1-10 alkyl, C₆₋₁₀-aryl, C₇₋₁₂-alkylaryl, or C₇₋₁₂-arylalkyl;

each X is a hydrogen atom, —OR, a halogen atom, or an R group;

R is C₁₋₁₀ alkyl

each R⁴ is H or C₁₋₃-alkyl;

n is 0 to 3;

each W′ is aryl (e.g. phenyl), pyridyl, thiophenyl, or furyl optionallysubstituted by up to 2 groups R⁵;

each R⁵ is C₁₋₁₀-alkyl or two adjacent R⁵ groups taken together form aphenyl ring fused to W′ or two adjacent R⁵ groups taken together formthe atoms necessary to form a carbazolyl group with the W′ group; and

each R¹⁸ is C₁₋₆-alkyl;

and wherein the two ligands forming the complex are identical.

In a preferred embodiment therefore the complex of the invention is offormula (III)

wherein

M is Zr or Hf;

each R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) wherein R³ is a C₁₋₆-alkylgroup or together two R³ groups form a C₃₋₇-cycloalkyl ring wherein saidring is optionally substituted by a C₁₋₆ alkyl group and q can be 1 or0;

L is SiR⁶ ₂;

R⁶ is C1-10 alkyl, C₆₋₁₀-aryl, C₇₋₁₂-alkylaryl, or C₇₋₁₂-arylalkyl;

each X is a hydrogen atom, OR, a halogen atom, or an R group;

R is C₁₋₁₀ alkyl

each R⁴ is H or C₁₋₃-alkyl;

n is 0 to 2;

p is 0 to 2;

each R⁵ is C₁₋₁₀-alkyl and

each R¹⁸ is C₁₋₆-alkyl;

and wherein the two ligands forming the complex are identical.

In a still further preferred embodiment, the invention provides acomplex of formula (IV)

in which:

M is Zr;

each R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) wherein R³ is a C₁₋₆-alkylgroup or together two R³ groups form a C₃₋₇-cycloalkyl ring wherein saidring is optionally substituted by a C₁₋₆ alkyl group and q can be 1 or0;

L is SiR⁶ ₂;

R⁶ is C₁₋₆ alkyl;

each X is a halogen atom, or methyl;

each R⁴ is H or methyl

p is 0 or 1; and

R⁵ is C₁₋₆ alkyl;

and wherein the two ligands forming the complex are identical.

In a further highly preferred embodiment, the invention provides acomplex of formula (V)

wherein p is 0 or 1;

L is SiR⁶ ₂;

R⁵ is a group C(R²)₃;

R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) wherein R³ is a C₁₋₆-alkyl group ortogether two R³ groups form a C₃₋₇-cycloalkyl ring wherein said ring isoptionally substituted by a C₁₋₆ alkyl group and q can be 1 or 0;

R² is a C1-6-alkyl group;

R³ is a C1-6-alkyl group or together two R³ groups form aC₃₋₇-cycloalkyl ring;

q is 0 or 1;

each X is a halogen atom, methoxy, or methyl; and

M is Zr;

and wherein the two ligands forming the complex are identical.

Some complexes of the invention are also new and form a further aspectof the invention. In particular, the invention provides a complex offormula (I), (II), (III), (IV) or (V) as herein before defined.Furthermore, it is submitted that ligands of formula (I) to (V) are alsonew and form a further aspect of the invention. The ligands do notcontain the MX₂ group and the Cp ring contains a double bond. Thus, aligand of formula (II) is represented by the formula:

For the avoidance of doubt, any narrower definition of a substituentoffered above can be combined with any other broad or narroweddefinition of any other substituent.

Throughout the disclosure above, where a narrower definition of asubstituent is presented, that narrower definition is deemed disclosedin conjunction with all broader and narrower definitions of othersubstituents in the application.

Synthesis

The ligands required to form the catalysts of the invention can besynthesised by any process and the skilled organic chemist would be ableto devise various synthetic protocols for the manufacture of thenecessary ligand materials. WO2006/097497 and the other prior artreferences mentioned above disclose the necessary chemistry and asherein incorporated by reference. Moreover, our examples set out asynthesis in which the tricyclic ring structure which forms the basis ofthe metallocenes of the invention is manufactured through thecombination of indane and 2-isobutylacrylic acid. It will be appreciatedthat by manipulating the nature of the acid, different R¹ groups can beprepared.

The process starts with indane acylation and subsequent cyclisation ofthe reaction product, followed by one pot aldol condensation andhydrogenation of the α,β-unsaturated ketone to give the desired2-(substituted)-3,5,6,7-tetrahydro-s-indacen-1(2H)-one. In brief, weform an unsubstituted indacen-1-one which we then alkylate in the 2position by aldol condensation with the desired R¹ carbaldehyde.

The rest of the synthesis is conventional and the synthetic protocolsdescribed in the examples will be readily adapted by the skilled man toallow the synthesis of a wide range of complexes.

The new synthetic protocols form a still yet further aspect of theinvention. Thus viewed from another aspect the invention provides aprocess for the preparation of a compound of formula (VI)

comprising reacting a compound of formula (VII)

with the compound R^(1′)CHO and hydrogenating the reaction product;wherein R^(1′) is as hereinbefore defined.

It is also possible to synthesize a compound of formula (VIII)

where R¹⁸ and n are as hereinbefore defined using the same chemistry inwhich the R¹⁸ group is present in the starting material.

The starting material can be prepared by an acylation reaction involvinga ring formation reaction as shown below.

The use of P₄O₁₀ and methanesulfonic acid is preferred to ensure thisreaction completes.

Cocatalyst

To form an active catalytic species it is normally necessary to employ acocatalyst as is well known in the art. Cocatalysts comprising anorganometallic compound of Group 13 metal, like organoaluminiumcompounds used to activate metallocene catalysts are suitable for use inthis invention.

The olefin polymerisation catalyst system of the invention comprises (i)a complex in which the metal ion is coordinated by a ligand of theinvention; and normally (ii) an aluminium alkyl compound (or otherappropriate cocatalyst), or the reaction product thereof. Thus thecocatalyst is preferably an alumoxane, like MAO or an alumoxane otherthan MAO.

Alternatively, however, the catalysts of the invention may be used withother cocatalysts, e.g. boron compounds such as B(C₆F₅)₃,C₆H₅N(CH₃)₂H:B(C₆F₅)₄, (C₆H₅)₃C:B(C₆F₅)₄ Or Ni(CN)₄[B(C₆F₅)₃]₄ ²⁻.

The use of aluminoxanes, especially MAO, is highly preferred.

Suitable amounts of cocatalyst will be well known to the skilled man.Typically Al to M molar ratios are from 1:1 to 1000:1 mol/mol.Preferably when an aluminium alkyl is used as a coctalyst, the molarratio of the aluminium in the activator to the transition metal in thecomplex is from 1 to 500 mol/mol, preferably from 10 to 400 mol/mol andin particular from 50 to 400 mol/mol.

Manufacture

The metallocene complex of the present invention can be used incombination with a suitable cocatalyst as a catalyst for thepolymerization of olefins, e.g. in a solvent such as toluene or analiphatic hydrocarbon, (i.e. for polymerization in solution), as it iswell known in the art. Preferably, polymerization of olefins, especiallypropylene, takes place in the condensed phase or in gas phase.

The catalyst of the invention is preferably in solid particulate form,e.g. as obtained for example by supporting on an inert organic orinorganic carrier, such as for example silica or in solid particulateform but unsupported.

The particulate support material used is preferably an organic orinorganic material, such as silica, alumina or zirconia or a mixed oxidesuch as silica-alumina, in particular silica, alumina or silica-alumina.

Especially preferably the support is a porous material so that thecomplex may be loaded into the pores of the support, e.g. using aprocess analogous to those described in WO94/14856 (Mobil), WO95/12622(Borealis) and WO2006/097497. The particle size is not critical but ispreferably in the range 5 to 200 μm, more preferably 20 to 80 μm. Theuse of these supports is routine in the art.

In one particular embodiment, no external carrier is used. In order toprovide the catalyst of the invention in solid form but without using anexternal carrier, it is preferred if a liquid liquid emulsion system isused. The process involves forming dispersing catalyst components (i)and (ii) in a solvent, and solidifying said dispersed droplets to formsolid particles.

In particular, the method involves preparing a solution of one or morecatalyst components; dispersing said solution in an solvent to form anemulsion in which said one or more catalyst components are present inthe droplets of the dispersed phase; immobilising the catalystcomponents in the dispersed droplets, in the absence of an externalparticulate porous support, to form solid particles comprising the saidcatalyst, and optionally recovering said particles.

This process enables the manufacture of active catalyst particles withimproved morphology, e.g. with a predetermined spherical shape andparticle size and without using any added external porous supportmaterial, such as an inorganic oxide, e.g. silica. Also desirablesurface properties can be obtained.

By the term “preparing a solution of one or more catalyst components” ismeant that the catalyst forming compounds may be combined in onesolution which is dispersed to the immiscible solvent, or,alternatively, at least two separate catalyst solutions for each part ofthe catalyst forming compounds may be prepared, which are then dispersedsuccessively to the solvent.

In a preferred method for forming the catalyst at least two separatesolutions for each or part of said catalyst may be prepared, which arethen dispersed successively to the immiscible solvent.

More preferably, a solution of the complex comprising the transitionmetal compound and the cocatalyst is combined with the solvent to forman emulsion wherein that inert solvent forms the continuous liquid phaseand the solution comprising the catalyst components forms the dispersedphase (discontinuous phase) in the form of dispersed droplets. Thedroplets are then solidified to form solid catalyst particles, and thesolid particles are separated from the liquid and optionally washedand/or dried. The solvent forming the continuous phase may be immiscibleto the catalyst solution at least at the conditions (e.g. temperatures)used during the dispersing step.

The term “immiscible with the catalyst solution” means that the solvent(continuous phase) is fully immiscible or partly immiscible i.e. notfully miscible with the dispersed phase solution.

Preferably said solvent is inert in relation to the compounds of thecatalyst system to be produced. Full disclosure of the necessary processcan be found in WO03/051934 which is herein incorporated by reference.

The inert solvent must be chemically inert at least at the conditions(e.g. temperature) used during the dispersing step. Preferably, thesolvent of said continuous phase does not contain dissolved therein anysignificant amounts of catalyst forming compounds. Thus, the solidparticles of the catalyst are formed in the droplets from the compoundswhich originate from the dispersed phase (i.e. are provided to theemulsion in a solution dispersed into the continuous phase).

The terms “immobilisation” and “solidification” are used hereininterchangeably for the same purpose, i.e. for forming free flowingsolid catalyst particles in the absence of an external porousparticulate carrier, such as silica. The solidification happens thuswithin the droplets. Said step can be effected in various ways asdisclosed in said WO03/051934 Preferably solidification is caused by anexternal stimulus to the emulsion system such as a temperature change tocause the solidification. Thus in said step the catalyst component (s)remain “fixed” within the formed solid particles. It is also possiblethat one or more of the catalyst components may take part in thesolidification/immobilisation reaction.

Accordingly, solid, compositionally uniform particles having apredetermined particle size range can be obtained.

Furthermore, the particle size of the catalyst particles of theinvention can be controlled by the size of the droplets in the solution,and spherical particles with a uniform particle size distribution can beobtained.

The invention is also industrially advantageous, since it enables thepreparation of the solid particles to be carried out as a one-potprocedure. Continuous or semicontinuous processes are also possible forproducing the catalyst.

Dispersed Phase

The principles for preparing two phase emulsion systems are known in thechemical field. Thus, in order to form the two phase liquid system, thesolution of the catalyst component (s) and the solvent used as thecontinuous liquid phase have to be essentially immiscible at leastduring the dispersing step. This can be achieved in a known manner e.g.by choosing said two liquids and/or the temperature of the dispersingstep/solidifying step accordingly.

A solvent may be employed to form the solution of the catalyst component(s). Said solvent is chosen so that it dissolves said catalyst component(s). The solvent can be preferably an organic solvent such as used inthe field, comprising an optionally substituted hydrocarbon such aslinear or branched aliphatic, alicyclic or aromatic hydrocarbon, such asa linear or cyclic alkane, an aromatic hydrocarbon and/or a halogencontaining hydrocarbon.

Examples of aromatic hydrocarbons are toluene, benzene, ethylbenzene,propylbenzene, butylbenzene and xylene. Toluene is a preferred solvent.The solution may comprise one or more solvents. Such a solvent can thusbe used to facilitate the emulsion formation, and usually does not formpart of the solidified particles, but e.g. is removed after thesolidification step together with the continuous phase.

Alternatively, a solvent may take part in the solidification, e.g. aninert hydrocarbon having a high melting point (waxes), such as above 40°C., suitably above 70° C., e.g. above 80° C. or 90° C., may be used assolvents of the dispersed phase to immobilise the catalyst compoundswithin the formed droplets.

In another embodiment, the solvent consists partly or completely of aliquid monomer, e.g. liquid olefin monomer designed to be polymerised ina “prepolymerisation” immobilisation step.

Continuous Phase

The solvent used to form the continuous liquid phase is a single solventor a mixture of different solvents and may be immiscible with thesolution of the catalyst components at least at the conditions (e.g.temperatures) used during the dispersing step. Preferably said solventis inert in relation to said compounds.

The term “inert in relation to said compounds” means herein that thesolvent of the continuous phase is chemically inert, i.e. undergoes nochemical reaction with any catalyst forming component. Thus, the solidparticles of the catalyst are formed in the droplets from the compoundswhich originate from the dispersed phase, i.e. are provided to theemulsion in a solution dispersed into the continuous phase.

It is preferred that the catalyst components used for forming the solidcatalyst will not be soluble in the solvent of the continuous liquidphase. Preferably, said catalyst components are essentially insoluble insaid continuous phase forming solvent.

Solidification takes place essentially after the droplets are formed,i.e. the solidification is effected within the droplets e.g. by causinga solidifying reaction among the compounds present in the droplets.Furthermore, even if some solidifying agent is added to the systemseparately, it reacts within the droplet phase and no catalyst formingcomponents go into the continuous phase.

The term “emulsion” used herein covers both bi- and multiphasic systems.

In a preferred embodiment said solvent forming the continuous phase isan inert solvent including a halogenated organic solvent or mixturesthereof, preferably fluorinated organic solvents and particularly semi,highly or perfluorinated organic solvents and functionalised derivativesthereof. Examples of the above-mentioned solvents are semi, highly orperfluorinated hydrocarbons, such as alkanes, alkenes and cycloalkanes,ethers, e.g. perfluorinated ethers and amines, particularly tertiaryamines, and functionalised derivatives thereof. Preferred are semi,highly or perfluorinated, particularly perfluorinated hydrocarbons, e.g.perfluorohydrocarbons of e.g. C3-C30, such as C4-C10. Specific examplesof suitable perfluoroalkanes and perfluorocycloalkanes includeperfluoro-hexane, -heptane, -octane and -(methylcyclohexane). Semifluorinated hydrocarbons relates particularly to semifluorinatedn-alkanes, such as perfluoroalkyl-alkane.

“Semi fluorinated” hydrocarbons also include such hydrocarbons whereinblocks of —C—F and —C—H alternate. “Highly fluorinated” means that themajority of the —C—H units are replaced with —C—F units.“Perfluorinated” means that all —C—H units are replaced with —C—F units.See the articles of A. Enders and G. Maas in “Chemie in unserer Zeit”,34. Jahrg. 2000, Nr.6, and of Pierandrea Lo Nostro in “Advances inColloid and Interface Science”, 56 (1995) 245-287, Elsevier Science.

Dispersing Step

The emulsion can be formed by any means known in the art: by mixing,such as by stirring said solution vigorously to said solvent forming thecontinuous phase or by means of mixing mills, or by means of ultra sonicwave, or by using a so called phase change method for preparing theemulsion by first forming a homogeneous system which is then transferredby changing the temperature of the system to a biphasic system so thatdroplets will be formed.

The two phase state is maintained during the emulsion formation step andthe solidification step, as, for example, by appropriate stirring.

Additionally, emulsifying agents/emulsion stabilisers can be used,preferably in a manner known in the art, for facilitating the formationand/or stability of the emulsion. For the said purposes e.g.surfactants, e.g. a class based on hydrocarbons (including polymerichydrocarbons with a molecular weight e.g. up to 10 000 and optionallyinterrupted with a heteroatom(s)), preferably halogenated hydrocarbons,such as semi- or highly fluorinated hydrocarbons optionally having afunctional group selected e.g. from —OH, —SH, NH₂, NR″₂. —COOH, —COONH₂,oxides of alkenes, —CR″═CH₂, where R″ is hydrogen, or C1-C20 alkyl,C2-20-alkenyl or C2-20-alkynyl group, oxo-groups, cyclic ethers and/orany reactive derivative of these groups, like alkoxy, or carboxylic acidalkyl ester groups, or, preferably semi-, highly- or perfluorinatedhydrocarbons having a functionalised terminal, can be used. Thesurfactants can be added to the catalyst solution, which forms thedispersed phase of the emulsion, to facilitate the forming of theemulsion and to stabilize the emulsion.

Alternatively, an emulsifying and/or emulsion stabilising aid can alsobe formed by reacting a surfactant precursor bearing at least onefunctional group with a compound reactive with said functional group andpresent in the catalyst solution or in the solvent forming thecontinuous phase. The obtained reaction product acts as the actualemulsifying aid and or stabiliser in the formed emulsion system.

Examples of the surfactant precursors usable for forming said reactionproduct include e.g. known surfactants which bear at least onefunctional group selected e.g. from —OH, —SH, NH₂, NR″₂. —COOH, —COONH₂,oxides of alkenes, —CR″═CH₂, where R″ is hydrogen, or C1-C20 alkyl,C2-20-alkenyl or C2-20-alkynyl group, oxo-groups, cyclic ethers with 3to 5 ring atoms, and/or any reactive derivative of these groups, likealkoxy or carboxylic acid alkyl ester groups; e.g. semi-, highly orperfluorinated hydrocarbons bearing one or more of said functionalgroups. Preferably, the surfactant precursor has a terminalfunctionality as defined above.

The compound reacting with such surfactant precursor is preferablycontained in the catalyst solution and may be a further additive or oneor more of the catalyst forming compounds. Such compound is e.g. acompound of group 13 (e.g. MAO and/or an aluminium alkyl compound and/ora transition metal compound).

If a surfactant precursor is used, it is preferably first reacted with acompound of the catalyst solution before the addition of the transitionmetal compound. In one embodiment e.g. a highly fluorinated C1-n(suitably C4-30- or C5-15) alcohol (e.g. highly fluorinated heptanol,octanol or nonanol), oxide (e.g. propenoxide) or acrylate ester isreacted with a cocatalyst to form the “actual” surfactant. Then, anadditional amount of cocatalyst and the transition metal compound isadded to said solution and the obtained solution is dispersed to thesolvent forming the continuous phase. The “actual” surfactant solutionmay be prepared before the dispersing step or in the dispersed system.If said solution is made before the dispersing step, then the prepared“actual” surfactant solution and the transition metal solution may bedispersed successively (e.g. the surfactant solution first) to theimmiscible solvent, or be combined together before the dispersing step.

Solidification

The solidification of the catalyst component(s) in the disperseddroplets can be effected in various ways, e.g. by causing oraccelerating the formation of said solid catalyst forming reactionproducts of the compounds present in the droplets. This can be effected,depending on the used compounds and/or the desired solidification rate,with or without an external stimulus, such as a temperature change ofthe system.

In a particularly preferred embodiment, the solidification is effectedafter the emulsion system is formed by subjecting the system to anexternal stimulus, such as a temperature change. Temperature differencesof e.g. 5 to 100° C., such as 10 to 100° C., or 20 to 90° C., such as 50to 90° C.

The emulsion system may be subjected to a rapid temperature change tocause a fast solidification in the dispersed system. The dispersed phasemay e.g. be subjected to an immediate (within milliseconds to fewseconds) temperature change in order to achieve an instantsolidification of the component (s) within the droplets. The appropriatetemperature change, i.e. an increase or a decrease in the temperature ofan emulsion system, required for the desired solidification rate of thecomponents cannot be limited to any specific range, but naturallydepends on the emulsion system, i. a. on the used compounds and theconcentrations/ratios thereof, as well as on the used solvents, and ischosen accordingly. It is also evident that any techniques may be usedto provide sufficient heating or cooling effect to the dispersed systemto cause the desired solidification.

In one embodiment the heating or cooling effect is obtained by bringingthe emulsion system with a certain temperature to an inert receivingmedium with significantly different temperature, e.g. as stated above,whereby said temperature change of the emulsion system is sufficient tocause the rapid solidification of the droplets. The receiving medium canbe gaseous, e.g. air, or a liquid, preferably a solvent, or a mixture oftwo or more solvents, wherein the catalyst component (s) is (are)immiscible and which is inert in relation to the catalyst component (s).For instance, the receiving medium comprises the same immiscible solventused as the continuous phase in the first emulsion formation step.

Said solvents can be used alone or as a mixture with other solvents,such as aliphatic or aromatic hydrocarbons, such as alkanes. Preferablya fluorinated solvent as the receiving medium is used, which may be thesame as the continuous phase in the emulsion formation, e.g.perfluorinated hydrocarbon.

Alternatively, the temperature difference may be effected by gradualheating of the emulsion system, e.g. up to 10° C. per minute, preferably0.5 to 6° C. per minute and more preferably in 1 to 5° C. per minute.

In case a melt of e.g. a hydrocarbon solvent is used for forming thedispersed phase, the solidifcation of the droplets may be effected bycooling the system using the temperature difference stated above.

Preferably, the “one phase” change as usable for forming an emulsion canalso be utilised for solidifying the catalytically active contentswithin the droplets of an emulsion system by, again, effecting atemperature change in the dispersed system, whereby the solvent used inthe droplets becomes miscible with the continuous phase, preferably afluorous continuous phase as defined above, so that the droplets becomeimpoverished of the solvent and the solidifying components remaining inthe “droplets” start to solidify. Thus the immisciblity can be adjustedwith respect to the solvents and conditions (temperature) to control thesolidification step.

The miscibility of e.g. organic solvents with fluorous solvents can befound from the literature and be chosen accordingly by a skilled person.Also the critical temperatures needed for the phase change are availablefrom the literature or can be determined using methods known in the art,e.g. the Hildebrand-Scatchard-Theorie. Reference is also made to thearticles of A. Enders and G. and of Pierandrea Lo Nostro cited above.

Thus according to the invention, the entire or only part of the dropletmay be converted to a solid form. The size of the “solidified” dropletmay be smaller or greater than that of the original droplet, e.g. if theamount of the monomer used for the prepolymerisation is relativelylarge.

The solid catalyst particles recovered can be used, after an optionalwashing step, in a polymerisation process of an olefin. Alternatively,the separated and optionally washed solid particles can be dried toremove any solvent present in the particles before use in thepolymerisation step. The separation and optional washing steps can beeffected in a known manner, e.g. by filtration and subsequent washing ofthe solids with a suitable solvent.

The droplet shape of the particles may be substantially maintained. Theformed particles may have an average size range of 1 to 500 μm, e.g. 5to 500 μm, advantageously 5 to 200 μm or 10 to 150 μm. Even an averagesize range of 5 to 60 μm is possible. The size may be chosen dependingon the polymerisation the catalyst is used for. Advantageously, theparticles are essentially spherical in shape, they have a low porosityand a low surface area.

The formation of solution can be effected at a temperature of 0-100° C.,e.g. at 20-80° C. The dispersion step may be effected at −20° C.-100°C., e.g. at about −10-70° C., such as at −5 to 30° C., e.g. around 0° C.

To the obtained dispersion an emulsifying agent as defined above, may beadded to improve/stabilise the droplet formation. The solidification ofthe catalyst component in the droplets is preferably effected by raisingthe temperature of the mixture, e.g. from 0° C. temperature up to 100°C., e.g. up to 60-90° C., gradually. E.g. in 1 to 180 minutes, e.g. 1-90or 5-30 minutes, or as a rapid heat change. Heating time is dependent onthe size of the reactor.

During the solidification step, which is preferably carried out at about60 to 100° C., preferably at about 75 to 95° C., (below the boilingpoint of the solvents) the solvents may preferably be removed andoptionally the solids are washed with a wash solution, which can be anysolvent or mixture of solvents such as those defined above and/or usedin the art, preferably a hydrocarbon, such as pentane, hexane orheptane, suitably heptane. The washed catalyst can be dried or it can beslurried into an oil and used as a catalyst-oil slurry in polymerisationprocess.

All or part of the preparation steps can be done in a continuous manner.Reference is made to WO2006/069733 describing principles of such acontinuous or semicontinuous preparation methods of the solid catalysttypes, prepared via emulsion/solidification method.

Polymerisation

The olefin polymerized using the catalyst of the invention is preferablypropylene or a higher alpha-olefin. It may also be ethylene or a mixtureof ethylene and an α-olefin. Alternatively, it may also be mixture ofalpha olefins, for example C₂₋₂₀ olefins, e.g. ethylene, propylene,1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene etc. The olefinspolymerized in the method of the invention may include any compoundwhich includes unsaturated polymerizable groups. Thus for exampleunsaturated compounds, such as C₆₋₂₀ olefins (including cyclic andpolycyclic olefins (e.g. norbornene)), and polyenes, especially C₄₋₂₀dienes, may be included in a comonomer mixture with lower olefins, e.g.C₂₋₅ α-olefins. Diolefins (i.e. dienes) are suitably used forintroducing long chain branching into the resultant polymer. Examples ofsuch dienes include α,ω linear dienes such as 1,5-hexadiene,1,6-heptadiene, 1,8-nonadiene, 1,9-decadiene, etc.

The catalysts of the present invention are particularly suited for usein the manufacture of polypropylene polymers, either homopolymers orespecially copolymers thereof. Most especially, the catalyst are used tomanufacture random copolymers of propylene, e.g. random copolymers ofpropylene and ethylene.

As comonomers to propylene are preferably used ethylene, or higherolefins, e.g. C4-C12 olefins, like 1-butene, 1-hexene, 1-octene or anymixtures thereof, preferably ethylene. It is especially preferred if thepolymer is a propylene ethylene random copolymer. The ethylene contentin such a polymer may be up to 7 wt %, e.g. 0.5 to 5 wt %.

Polymerization in the method of the invention may be effected in one ormore, e.g. 1, 2 or 3, polymerization reactors, using conventionalpolymerization techniques, e.g. gas phase, solution phase, slurry orbulk polymerization.

In general, a combination of slurry (or bulk) and at least one gas phasereactor is often preferred, particularly with the reactor order beingslurry (or bulk) then one or more gas phase reactors.

In case of propylene polymerisation for slurry reactors, the reactiontemperature will generally be in the range 60 to 110° C. (e.g. 60-90°C.), the reactor pressure will generally be in the range 5 to 80 bar(e.g. 20-60 bar), and the residence time will generally be in the range0.1 to 5 hours (e.g. 0.3 to 2 hours). The monomer is usually used asreaction medium.

For gas phase reactors, the reaction temperature used will generally bein the range 60 to 115° C. (e.g. 70 to 110° C.), the reactor pressurewill generally be in the range 10 to 25 bar, and the residence time willgenerally be 0.5 to 8 hours (e.g. 0.5 to 4 hours). The gas used will bethe monomer optionally as mixture with a non-reactive gas such asnitrogen or propane. In addition to actual polymerisation steps andreactors, the process can contain any additional polymerisation steps,like prepolymerisation step, and any further after reactor handlingsteps as known in the art.

Generally the quantity of catalyst used will depend upon the nature ofthe catalyst, the reactor types and conditions and the propertiesdesired for the polymer product. As is well known in the art hydrogencan be used for controlling the molecular weight of the polymer. It isparticularly notable that the catalyst of the present invention performsexceptionally well over a wide range of hydrogen concentration usedduring the polymerisation process, which makes the catalyst beneficialto be used for productions of a wide range of polymers. This forms afurther aspect of the invention. The catalysts are useful at higherhydrogen concentrations as well with lower hydrogen concentrations toget polymer with higher molecular weight. The activity of the catalystsof the invention is also very high as well as the catalyst productivity.

The propylene polymers made using the catalysts of the invention form astill yet further aspect of the invention. The catalysts of theinvention enable the formation of high molecular weight, low xylenesoluble polymers which also possess high isotacticity. MFR₂₁ valuesbelow 7 g/10 min or even below 4 g/10 min (230° C., 216 kg load, ISO1133), which indicate very low MFR₂ values, well below 0.3 g/10 min,even values below 0.1 g/10 min (230° C., 2.16 kg load, ISO1133) whichcan be obtained with still good productivity.

Preferably, xylene soluble content of the polymer made by the catalystof the invention is less than 1 wt %, more preferably 0.7 wt % or lessand even more preferably less than 0.5 wt %. This is achieved even whenethylene content is in the range of 1 to 5 wt %.

Thus viewed from another aspect the invention provides a randompropylene ethylene copolymer having up to 10 wt % of ethylene having aMw of at least 300,000 and a xylene soluble fraction of less than 0.75wt %.

Ideally the ethylene content should be 5 wt % or less, e.g. 0.5 to 5 wt%. Ethylene should be the only comonomer present. The molecular weightof the polypropylene can be at least 300,000, preferably at least400,000, or even at least 500,000.

The polymers made by the catalysts of the invention are useful in allkinds of end articles such as pipes, films (cast, blown or BOPP films),fibers, moulded articles (e.g. injection moulded, blow moulded,rotomoulded articles), extrusion coatings and so on.

The invention will now be illustrated by reference to the followingnon-limiting Examples.

Measurement Methods: Al and Zr Determination (ICP-Method)

The elementary analysis of a catalyst was performed by taking a solidsample of mass, M, cooling over dry ice. Samples were diluted up to aknown volume, V, by dissolving in nitric acid (HNO₃, 65%, 5% of V) andfreshly deionised (DI) water (5% of V). The solution was then added tohydrofluoric acid (HF, 40%, 3% of V), diluted with DI water up to thefinal volume, V, and left to stabilise for two hours. The analysis wasrun at room temperature using a Thermo Elemental IRIS Advantage XUVInductively Coupled Plasma—Atomic Excitation Spectrometer (ICP-AES)which was calibrated immediately before analysis using a blank (asolution of 5% HNO₃, 3% HF in DI water), a low standard (10 ppm Al in asolution of 5% HNO₃, 3% HF in DI water), a high standard (50 ppm Al, 20ppm Zr in a solution of 5% HNO₃, 3% HF in DI water) and a qualitycontrol sample (20 ppm Al, 10 ppm Zr in a solution of 5% HNO₃, 3% HF inDI water). The content of zirconium was monitored using the 339.198 nmline, the content of aluminium via the 396.152 nm line and the potassiumusing the 766.490 nm line. The reported values, required to be between 0and 100, or further dilution is required, are an average of threesuccessive aliquots taken from the same sample and are related back tothe original catalyst using equation 1.

$\begin{matrix}{C = \frac{R \times V}{M}} & {{Equation}\mspace{14mu} 1}\end{matrix}$

Where:

-   -   C is the concentration in ppm, related to % content by a factor        of 10,000    -   R is the reported value from the ICP-AES    -   V is the total volume of dilution in ml    -   M is the original mass of sample in g        If dilution was required then this also needs to be taken into        account by multiplication of C by the dilution factor.

Intrinsic Viscosity

Polymer samples were dissolved in decalin at the concentration of 1mg/ml and at the temperature of 135° C. The relative viscosity of thedilute polymer solution was measured according to the ISO1628-1 by useof an Automated Ubbelohde Capillary Viscometer; LAUDA PVS1. The relativeviscosity of the dissolved polymer solution was determined as a ratio ofthe measured kinematic viscosities of the polymer solution and the puresolvent. Intrinsic viscosity was calculated from a single viscositymeasurement at known concentration by use of Huggins equation and knownHuggins constant.

Melting Temperature T_(m) [° C.] and Crystallisation Temperature T_(c)[° C.]:

Melting temperature (T_(m)), crystallization temperature (T_(c)), weremeasured (according to ISO 11357-3:1999) with Mettler TA820 differentialscanning calorimetry (DSC) on 5 to 10 mg, typically 8±0.5 mg samples.Both crystallization and melting curves were obtained during 10° C./mincooling and heating scans between 30° C. and 225° C. Melting andcrystallization temperatures were taken as the peaks of endotherms andexotherms. The peak temperature of the second heating scan was taken asthe melting temperature.

Melt Flow Rate

The melt flow rate (MFR) is determined according to ISO 1133 and isindicated in g/10 min. The MFR is an indication of the flowability, andhence the processability, of the polymer. The higher the melt flow rate,the lower the viscosity of the polymer. The MFR is determined at 230° C.and may be determined at different loadings such as 2.16 kg (MFR₂) or21.6 kg (MFR₂₁).

GPC:

Molecular weight averages, molecular weight distribution, andpolydispersity index (Mn, Mw, MWD)Molecular weight averages (Mw, Mn), Molecular weight distribution (MWD)and its broadness, described by polydispersity index, PDI=Mw/Mn (whereinMn is the number average molecular weight and Mw is the weight averagemolecular weight) were determined by Gel Permeation Chromatography (GPC)according to ISO 16014-4:2003 and ASTM D 6474-99. A Waters GPCV2000instrument, equipped with differential refractive index detector andonline viscosimeter was used with 2×GMHXL-HT and 1× G7000HXL-HT TSK-gelcolumns from Tosoh Bioscience and 1,2,4-trichlorobenzene (TCB,stabilized with 250 mg/L 2,6-Di tert butyl-4-methyl-phenol) as solventat 140° C. and at a constant flow rate of 1 mL/min. 209.5 μL of samplesolution were injected per analysis. The column set was calibrated usinguniversal calibration (according to ISO 16014-2:2003) with at least 15narrow MWD polystyrene (PS) standards in the range of 1 kg/mol to 12 000kg/mol. Mark Houwink constants for PS, PE and PP used are as per ASTM D6474-99. All samples were prepared by dissolving 0.5-4.0 mg of polymerin 4 mL (at 140° C.) of stabilized TCB (same as mobile phase) andkeeping for max. 3 hours at max. 160° C. with continuous gentle shakingprior sampling into the GPC instrument.

Xylene Solubles

2.0 g of polymer is dissolved in 250 ml p-xylene at 135° C. underagitation. After 30 minutes the solution is allowed to cool for 15minutes at ambient temperature and then allowed to settle for 30 minutesat 25° C. The solution is filtered with filter paper into two 100 mlflasks. The solution from the first 100 ml vessel is evaporated innitrogen flow and the residue is dried under vacuum at 90° C. untilconstant weight is reached.

XS %=(100·m·Vo)/(mo·v);

mo=initial polymer amount (g); m=weight of residue (g); Vo=initialvolume (ml); v=volume of analysed sample (ml).

Catalyst Activity

The catalyst activity was calculated on the basis of following formula:

${{Catalyst}\mspace{14mu} {Activity}\mspace{14mu} \left( {{kg}\text{/}g^{*}h} \right)} = \frac{{amount}\mspace{14mu} {of}\mspace{14mu} {polymer}\mspace{14mu} {produced}\mspace{14mu} ({kg})}{{catalyst}\mspace{14mu} {loading}\mspace{14mu} (g) \times {polymerisation}\mspace{14mu} {time}\mspace{14mu} (h)}$

Comonomer Content by ¹³C NMR Quantification of Microstructure by NMRSpectroscopy

Quantitative nuclear-magnetic resonance (NMR) spectroscopy was used toquantify the comonomer content of the polymers.Quantitative ¹³C {¹H} NMR spectra were recorded in the solution-stateusing a Bruker Advance III 400 NMR spectrometer operating at 400.15 and100.62 MHz for ¹H and ¹³C respectively. All spectra were recorded usinga ¹³C optimised 10 mm extended temperature probehead at 125° C. usingnitrogen gas for all pneumatics. Approximately 200 mg of material wasdissolved in 3 ml of 1,2-tetrachloroethane-d₂ (TCE-d₂) along withchromium-(III)-acetylacetonate (Cr(acac)₃) resulting in a 65 mM solutionof relaxation agent in solvent as described in G. Singh, A. Kothari, V.Gupta, Polymer Testing 2009, 28(5), 475.To ensure a homogenous solution, after initial sample preparation in aheat block, the NMR tube was further heated in a rotatory oven for atleast 1 hour. Upon insertion into the magnet the tube was spun at 10 Hz.This setup was chosen primarily for the high resolution andquantitatively needed for accurate ethylene content quantification.Standard single-pulse excitation was employed without NOE, using anoptimised tip angle, 1 s recycle delay and a bi-level WALTZ16 decouplingscheme as described in Z. Zhou, R. Kuemmerle, X. Qiu, D. Redwine, R.Cong, A. Taha, D. Baugh, B. Winniford, J. Mag. Reson. 187 (2007) 225 andV. Busico, P. Carbonniere, R. Cipullo, C. Pellecchia, J. Severn, G.Talarico, Macromol. Rapid Commun. 2007, 28, 1128. A total of 6144 (6k)transients were acquired per spectra. Quantitative ¹³C {¹H} NMR spectrawere processed, integrated and relevant quantitative propertiesdetermined from the integrals. All chemical shifts were indirectlyreferenced to the central methylene group of the ethylene block (EEE) at30.00 ppm using the chemical shift of the solvent. This approach allowedcomparable referencing even when this structural unit was not present.With characteristic signals corresponding to 2,1 erythro regio defectsobserved (as described in L. Resconi, L. Cavallo, A. Fait, F.Piemontesi, Chem. Rev. 2000, 100 (4), 1253, in Cheng, H. N.,Macromolecules 1984, 17, 1950, and in W-J. Wang and S. Zhu,Macromolecules 2000, 33 1157) the correction for the influence of theregio defects on determined properties was required. Characteristicsignals corresponding to other types of regio defects were not observed.Characteristic signals corresponding to the incorporation of ethylenewere observed (as described in Cheng, H. N., Macromolecules 1984, 17,1950) and the comonomer fraction calculated as the fraction of ethylenein the polymer with respect to all monomer in the polymer:

fE=(E/(P+E)

The comonomer fraction was quantified using the method of W-J. Wang andS. Zhu, Macromolecules 2000, 33 1157, through integration of multiplesignals across the whole spectral region in the ¹³C{¹H} spectra. Thismethod was chosen for its robust nature and ability to account for thepresence of regio-defects when needed. Integral regions were slightlyadjusted to increase applicability across the whole range of encounteredcomonomer contents.The mole percent comonomer incorporation was calculated from the molefraction:

E [mol %]=100*fE

The weight percent comonomer incorporation was calculated from the molefraction:

E [wt %]=100*(fE*28.06)/((fE*28.06)+((1−fE)*42.08))

EXAMPLES General Procedures and Starting Materials

All manipulations with air and moisture sensitive compounds wereperformed either in an atmosphere of thoroughly purified argon using astandard Schlenk technique or in a controlled atmosphere Glove Box(Mecaplex, VAC or M. Braun). Tetrahydrofurane (Merck) and diethyl ether(Merck) for synthesis were purified by distillation over LiAlH₄ and keptover sodium benzophenone ketyl. Toluene (Merck) and hexanes (Merck) weredistilled and stored over CaH₂ or Na/K alloy. Dichloromethane (Merck)for organometallic synthesis as well as CD₂Cl₂ (Merck) were distilledand stored over CaH₂. Chloroform-d (Merck) was distilled over P₄O₁₀ andstored over molecular sheves (3 Å). Methanol (Merck), dimethylformamide(Merck), dichloromethane (Merck), ethyl acetoacetate (Acros),isobutylbromide (Merck), bis(trimethylsilyl)amine (Merck),para-toluenesulfonic acid (Aldrich), paraformaldehyde (Merck),methanesulfonic acid (Aldrich), ZrCl₄(THF)₂ (Aldrich), CuBr (Acros), 2.5M ^(n)BuLi in hexanes (Chemetall), Pd(dba)₂ (Aldrich), NaBH₄ (Acros),dicyclohexyl(2′,6′-dimethoxybiphenyl-2-yl)phosphine (Aldrich), 60%suspension of NaH in mineral oil (Aldrich), 4-tert-butylphenylboronicacid (Aldrich), anhydrous powdered AlCl₃ (Merck), dichlorodimethylsilane(Merck), K₃PO₄ (Fluka), P₄O₁₀ (Merck), Cyclohexanecarbaldehyde(Aldrich), 10% Pd on charcoal (Aldrich), hydrogen gas (Linde), KOH(Merck), Na₂SO₄ (Akzo Nobel), TsOH (Aldrich), 12 M HCl (Reachim,Russia), 96% ethanol (Merck), Silica Gel 60 40-63 μm (Merck) were usedas obtained. Celite 503 (Aldrich) was dried in vacuum at 200° C. beforeuse. 3,5,6,7-Tetrahydro-s-indacen-1(2H)-one was synthesized viaacylation of indan (ABCR) by 3-chloropropyonyl chloride (Acros) followedby cyclization of the formed acylation product in H₂SO₄ (Reachim,Russia) as described in [Woodward, R. B.; Hoye, T. R. J. Am. Chem. Soc.1977, 99, 8007].

Analytical and semi-preparative liquid chromatography was performedusing Waters Delta 600 HPLC system including 996 Photodiode ArrayDetector, Nova-Pack C18 or HR Silica (60A, 6 μm, 3.9 and 19×300 mm) andSymmetry C18 (5 μm, 4.6×250 mm) columns. ¹H NMR spectra were recordedwith a Bruker Avance-400 for 1-10% solutions in deuterated solvents.Chemical shifts for ¹H were measured relatively to TMS. The assignmentwas made on the evidence of double resonance and NOE experiments. C, Hmicroanalyses were done using CHN-O-Rapid analyzer (Heracus).

Catalyst 1 Rac- andmeso-1,1′-Dimethylsilylene-bis[2-isobutyl-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacenyl]zirconiumdichlorides Preparation Example 1 Ethyl 2-acetyl-4-methylpentanoate

To a solution of 100 g (0.77 mol) of ethyl acetoacetate in 500 ml of DMF30.7 g (0.77 mol) of 60% suspension of NaH in mineral oil was added insmall portions by vigorous stirring at 60° C. This mixture wasadditionally stirred for 1 h, and then 105.5 g (0.77 mol) ofisobutylbromide was added. The resulting mixture was stirred for 3 h at90° C., then cooled to room temperature, and 1500 ml of cold water wasadded. The product was extracted by 3×300 ml of dichloromethane. Thecombined organic extract was evaporated at reduced pressure using rotaryevaporator. Fractional rectification of the residue gave the titleproduct, b.p. 75-80° C./4 mm Hg. Yield 80.5 g (56%).

Anal. calc. for C₁₀H₁₈O₃: C, 64.49; H, 9.74. Found: C, 64.20; H, 3.81.

¹H NMR (CDCl₃): δ 4.13 (q, J=7.2 Hz, 2H, CH₂Me), 3.44 (dd, J=8.3 Hz,J=6.6 Hz, 1H, CHCOMe), 2.16 (s, 3H, COMe), 1.74 (m, 1H, CHH′^(i)Pr),1.62 (CHH′^(i)Pr), 1.47 (sept, J=6.6 Hz, 1H, CHMe₂), 1.21 (t, J=7.2 Hz,3H, CH₂Me), 0.85 (d, J=6.6 Hz, 6H, CHMe₂).

Preparation Example 2 Ethyl 2-isobutylacrylate

Bis(trimethylsilyl)amine (9.50 g, 59.0 mmol) in 250 ml of THF wasmetallated by 23.5 ml (59.0 mmol) of 2.5 M ^(n)BuLi in hexanes at −78°C. This mixture was additionally stirred for 0.5 h at room temperature,then cooled again to −78° C., and 10.0 g (53.7 mmol) of ethyl2-acetyl-4-methylpentanoate was added. The resulting mixture was stirredfor 1 h at room temperature, cooled to −78° C., and 8.0 g (09.27 mmol)of paraformaldehyde was added. This mixture was stirred overnight atroom temperature, then filtered through glass frit (G3), and evaporatedto dryness. Fractional rectification of the residue gave the titleproduct, 50-55° C./4 mm Hg. Yield 6.50 g (78%).

Anal. calc. for C₉H₁₆O₂: C, 69.02; H, 10.32. Found: C, 69.09; H, 10.24.

¹H NMR (CDCl₃): δ 6.11 (m, 1H, ═CHH′), 5.43 (m, 1H, ═CHH′), 4.15 (q,J=7.1 Hz, 2H, CH₂Me), 2.14 (m, 2H, CH₂ ^(i)Bu), 1.75 (sept, J=6.7 Hz,1H, CHMe₂) 1.25 (t, J=7.1 Hz, 3H, CH₂Me), 0.85 (d, J=6.7 Hz, 6H, CHMe₂).

Preparation Example 3 2-Isobutylacrylic acid

Saponification of 6.32 g (40.4 mmol) ethyl 2-isobutylacrylate wascarried out 50 ml of 20% aqueous KOH at reflux. The obtained mixture wasacidified by aqueous HCl to pH=5-6, and the product was extracted by2×100 ml of dichloromethane. The organic extract was evaporated todryness to give 5.13 g (99%) 2-isobutylacrylic acid which was furtherused without an additional purification.

Preparation Example 4 2-Isobutyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

A mixture of 16.8 g (0.14 mol) of indane and 20.0 g (0.16 mmol) of2-isobutylacrylic acid was added top a mixture of 40 g of P₄O₁₀ and 200ml of methanesulfonic acid by vigorous stirring at 60° C. This mixturewas additionally stirred at this temperature, and the resulting mixturewas poured on 500 cm³ of ice. The product was extracted by 3×200 ml ofdichloromethane. The combined organic extract was washed by aqueousNaHCO₃, died over Na₂SO₄, and evaporated to dryness. The product wasisolated by flash chromatography on silica gel 60 (40-63 um, eluent:hexanes-dichloromethane=3:1, vol.). Yield 15.5 g (50%) of the titleproduct.

Anal. calc. for C₁₆H₂O: C, 84.16; H, 8.83. Found: C, 84.25; H, 8.88.

¹H NMR (CDCl₃): δ 7.69 (s, 1H, 8H), 7.28 (s, 1H, 4H), 3.28 (m, 1H),3.03-2.89 (m, 4H), 2.72 (m, 2H), 2.23-2.06 (m, 2H), 1.84 (m, 2H), 1.31(m, 1H), 0.95 (d, J=6.3 Hz, 6H, CHMe₂).

Preparation Example 52-isobutyl-4-Bromo-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

To a suspension of 14.6 g (110 mmol) of AlCl₃ in 40 ml ofdichloromethane a solution of 10.0 g (43.8 mmol) of2-isobutyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one in 25 ml ofdichloromethane was added dropwise by vigorous stirring at 0° C. Furtheron, 7.71 g (48.2 mmol) of bromine was added dropwise at thistemperature. The resulting mixture was stirred overnight at roomtemperature and then poured on 500 cm³ of ice. The product was extractedby 3×200 ml of dichloromethane. The combined organic extract was washedby water, aqueous NaHCO₃, dried over Na₂SO₄, and evaporated to dryness.The product was isolated by flash chromatography on silica gel 60 (40-63um, eluent: hexanes-dichloromethane=3:1, vol.). Yield 9.40 g (70%) ofthe title product.

Anal. calc. for C₁₆H₁₉BrO: C, 62.55; H, 6.23. Found: C, 62.70; H, 6.32.

¹H NMR (CDCl₃): δ 7.48 (s, 1H, 8-H), 3.21 (m, 1H), 2.95-3.05 (m, 4H),2.72 (m, 1H), 2.64 (m, 1H), 2.15-2.10 (m, 2H), 1.87-1.77 (m, 2H), 1.30(m, 1H), 0.97 (d, J=5.8 Hz, 6H, CHMe₂).

Preparation Example 6 4/8-Bromo-6-isobutyl-1,2,3,5-tetrahydro-s-indacene

To a solution of 7.40 g (32.4 mmol) of4-bromo-2-isobutyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one in 100 ml of amixture of THF and methanol (2:1, vol.) 3.50 g (92.5 mmol) of NaBH₄ wasadded in small portions by vigorous stirring for 30 min at 0° C. Thismixture was stirred overnight at room temperature and then evaporated todryness. The product was extracted by 2×150 ml of dichloromethane. Thecombined organic extract was dried over Na₂SO₄ and then evaporated todryness. To a solution of the residue in 100 ml of toluene 350 mg ofTsOH was added, and the resulting mixture was refluxed for 3 h. Theproduct was isolated by flash chromatography on silica gel 60 (40-63 um,eluent: hexanes). Yield 5.30 g (76%) of a ca. 1:5 mixture of4-bromo-6-isobutyl-1,2,3,5-tetrahydro-s-indacene and8-bromo-6-isobutyl-1,2,3,5-tetrahydro-s-indacene.

Anal. calc. for C₁₆H₁₉Br: C, 65.99; H, 6.58. Found: C, 54.15; H, 6.59.

¹H NMR (CDCl₃), 8-bromo-6-isobutyl-1,2,3,5-tetrahydro-s-indacene: δ 7.09(s, 1H, 4-H in tetrahydroindacene), 6.61 (m, 1H, 3-H intetrahydroindacene), 3.28 (s, 2H, 1,1′-H in tetrahydroindacene), 3.05(m, 2H, CH₂CH₂CH₂), 3.00 (m, 2H, CH₂CH₂CH₂), 2.38 (m, 2H, CH₂CH₂CH₂),2.15 (m, 2H, CH₂ ^(i)B u), 1.95 (sept, J=6.7 Hz, 1H, CHMe₂), 0.98 (d,J=6.7 Hz, 6H, CHMe₂).

Preparation Example 74/8-(4-tert-Butylphenyl)-6-isobutyl-1,2,3,5-tetrahydro-s-indacene

In argon atmosphere, a mixture of 2.13 g (12.0 mmol) of4-tert-butylphenylboronic acid, 2.90 g (9.96 mmol) of4/8-bromo-6-isobutyl-1,2,3,5-tetrahydro-s-indacene, 6.37 g (30.0 mmol)of K₃PO₄, 100 mg (0.17 mmol) of Pd(dba)₂, 150 mg (0.36 mmol) ofdicyclohexyl(2′,6′-dimethoxybiphenyl-2-yl)phosphine, and 30 ml of drytoluene was stirred for 12 h at 100° C. To the cooled resulting mixture100 ml of cold water was added. The product was extracted by 3×100 ml ofdichloromethane. The combined organic extract was dried over Na₂SO₄ andthen evaporated to dryness. The product was isolated by flashchromatography on silica gel 60 (40-63 um, eluent: hexanes). Yield 3.40g (98%) of a ca. 1:5 mixture of4-(4-tert-butylphenyl)-6-isobutyl-1,2,3,5-tetrahydro-s-indacene and8-(4-tert-butylphenyl)-6-isobutyl-1,2,3,5-tetrahydro-s-indacene.

Anal. calc. for C₂₆H₃₂: C, 90.64; H, 9.36. Found: C, 90.57; H, 9.49.

¹H NMR (CDCl₃),8-(4-tert-butylphenyl)-6-isobutyl-1,2,3,5-tetrahydro-s-indacene: δ 7.47(m, 2H, 2,6-H in 4-^(i)BuC₆H₄), 7.36 (m, 2H, 3,5-H in 4-^(i)BuC₆H₄),7.18 (s, 1H, 4-H in tetrahydroindacene), 6.53 (m, 1H, 3-H intetrahydroindacene), 3.23 (s, 2H, 1,1′-H in tetrahydroindacene), 3.01(m, 2H, CH₂CH₂CH₂), 2.84 (m, 2H, CH₂CH₂CH₂), 2.33 (d, J=7.2 Hz, 2H, CH₂^(i)Bu), 2.16-2.04 (m, 2H, CH₂CH₂CH₂), 1.87 (m, 1H, CHMe₂), 1.42 (s, 9H,^(t)Bu), 0.93 (d, J=6.6 Hz, 6H, CHMe₂).

Preparation Example 8 A mixture of rac- andmeso-bis[2-isobutyl-4-(4-tert-butylphenyl)-1,5,6,7-tetrahydro-s-indacen-1-yl](dimethyl)silanes

To a solution of 3.40 g (9.87 mmol) of4/8-(4-tert-butylphenyl)-6-isobutyl-1,2,3,5-tetrahydro-s-indacene in 80ml of ether 4.0 ml (10.0 mmol) of 2.5 M ^(n)BuLi in hexanes was added.This mixture was stirred for 12 h, and then 0.66 g (5.11 mmol) ofdichlorodimethylsilane was added. The resulting mixture was stirredovernight, and then 50 ml of cold water was added. The product wasextracted by 2×100 ml of dichloromethane. The combined organic extractwas dried over Na₂SO₄ and then evaporated to dryness. The product wasisolated by flash chromatography on silica gel 60 (40-63 um, eluent:hexanes). Yield 2.50 g (70%) of a ca. 1:1 mixture of rac- andmeso-bis[4-(4-tert-butylphenyl)-2-isobutyl-1,5,6,7-tetrahydro-s-indacen-1-yl](dimethyl)silanes.

Anal. calc. for C₅₄H₆₈Si: C, 87.03; H, 9.20. Found: C, 87.19; H, 9.35.

¹H NMR (CDCl₃): δ 7.46-7.42 (m, 8H), 7.39-7.34 (m, 8H), 7.26 (m, 2H),7.23 (m, 2H), 6.58 (m, 4H), 3.74 (m, 4H), 3.12-2.78 (m, 16H), 2.46-2.24(m, 8H), 2.04 (m, 8H), 1.94-1.75 (m, 4H), 1.40 (s, 18H), 1.39 (s, 18H),0.92 (d, J=6.6 Hz, 6H), 0.89 (d, J=6.6 Hz, 6H), 0.83 (d, J=6.6 Hz, 6H),0.81 (d, J=6.6 Hz, 6H), −0.17 (s, 3H), −0.22 (s, 6H), −0.30 (s, 3H).

Preparation Example 9 Rac- andmeso-1,1′-Dimethylsilylene-bis[2-isobutyl-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacenyl]zirconiumdichlorides

To a solution of 2.98 g (4.0 mmol) ofbis[4-(4-tert-butylphenyl)-2-isobutyl-1,5,6,7-tetrahydro-s-indacen-1-yl](dimethyl)silanein 60 ml of ether 3.20 ml (8.0 mmol) of 2.5 M ^(n)BuLi in hexanes wasadded. This mixture was stirred for 12 h, then cooled to −60° C., and1.51 g (4.0 mmol) of ZrCl₄(THF)₂ was added. The resulting mixture wasstirred for 12 h at room temperature. Further on, this mixture wasevaporated to dryness, and 40 ml of toluene was added. The formedsuspension was stirred for 5 h at 60° C., and then this hot mixturefiltered through glass frit (G4). The precipitate was additionallywashed by 10 ml of hot toluene. The combined filtrate was evaporated tothe reduced volume (ca. 20 ml) and then heated to 110° C. to dissolvesome solid product. Orange crystals precipitated from this solution atroom temperature were collected, washed by 5 ml of cold toluene, 10 mlof hexanes, and then dried in vacuum. This procedure gave 480 mg (13%)of pure meso-complex. The mother liquid was evaporated to dryness. Theresidue dried in vacuum was dissolved in 15 ml of ether. Yellow crystalsprecipitated from this solution at −30° C. were collected, washed by 5ml of cold ether, and dried in vacuum. This procedure gave 180 mg (5%)of pure rac-complex.

Rac-Complex:

Anal. calc. for C₅₄H₆₆Cl₂SiZr: C, 71.64; H, 7.35. Found: C, 71.49; H,7.45.

¹H NMR (CD₂Cl₂): δ 7.43-7.48 (m, 10H, 8-H in tetrahydroindacenyl and2,3,5,6-H in ^(t)BuC₆H₄), 6.65 (s, 2H, 3-H in tetrahydroindacenyl),3.00-2.77 (m, 8H, CH₂CH₂CH₂), 2.64 (dd, J=13.8 Hz, J=7.0 Hz, 2H,CHH′^(i)Bu), 2.08 (dd, J=13.8 Hz, J=7.5 Hz, 2H, CHH′^(i)Bu), 1.98 (m,4H, CH₂CH₂CH₂), 1.69 (m, 2H, CHMe₂), 1.35 (s, 18H, ^(t)Bu), 1.30 (s, 6H,SiMe₂), 0.86 (d, J=6.6 Hz, 6H, CHMeMe′), 0.78 (d, J=6.6 Hz, 6H, CHMeMe).

Meso-Complex:

Anal. calc. for C₅₄H₆₆Cl₂SiZr: C, 71.64; H, 7.35. Found: C, 71.60; H,7.42.

¹H NMR (CD₂Cl₂): δ 7.50 (s, 2H, 8-H in tetrahydroindacenyl), 7.44 (m,4H, 2,6-H in tetrahydroindacenyl), 7.40 (m, 4H, 3,5-H intetrahydroindacenyl), 6.49 (s, 2H, 3-H in tetrahydroindacenyl),2.95-2.65 (m, 8H, CH₂CH₂CH₂), 2.61 (dd, J=13.5 Hz, J=6.3 Hz, 2H,CHH′^(i)Bu), 2.44 (dd, J=13.5 Hz, J=8.0 Hz, 2H, CHH′^(i)Bu), 1.87 (m,4H, CH₂CH₂CH₂), 1.47 (s, 3H, SiMeMe′), 1.35 (s, 18H, ^(t)Bu), 1.18 (s,3H, SiMeMe′), 0.90 (d, J=6.6 Hz, 6H, CHMeMe′), 0.81 (d, J=6.6 Hz, 6H,CHMeMe′).

Catalyst 2Rac-1,1′-dimethylsilylene-bis[2-(cyclohexylmethyl)-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]zirconiumdichloride Preparation Example 102-(Cyclohexylmethyl)-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

In argon atmosphere, a 250 ml Berghof stainless steel autoclave withPTFE leaner was charged with 25.0 g (0.145 mol) of3,5,6,7-tetrahydro-s-indacen-1(2H)-one, 20.0 g (0.178 mmol) ofcyclohexanecarbaldehyde, 2.0 g (0.036 mol) of potassium hydroxide, 2.0 gof 10% Pd on charcoal and 150 ml of 96% ethanol. This reactor wasflashed by hydrogen, and then hydrogen was fed to a pressure of 3 atm.This mixture was stirred for 3 h at room temperature. The resultingmixture was filtered through glass frit (G3), and the precipitate wasadditionally washed by 50 ml of ethanol. The filtrate was evaporated todryness, and 500 ml was added to the residue. The crude product wasextracted by 3×200 ml of dichloromethane. The combined organic extractwas dried over Na₂SO₄ and then evaporated to dryness. The product wasisolated by flash chromatography on silica gel 60 (40-63 um, eluent:dichloromethane). Yield 36.5 g (94%).

Anal. calc. for C₁₉H₂₄O: C, 85.03; H, 9.01. Found: C, 85.17; H, 8.90.

¹H NMR (CDCl₃): δ 7.59 (s, 1H, 8-H in tetrahydroindacene), 7.28 (s, 1H,4-H in tetrahydroindacene), 3.27 (m, 1H, 2-H in tetrahydroindacene),2.95 (m, 4H, 5,5′,7,7′-H in tetrahydroindacene), 2.71-2.79 (m, 2H,6,6′-H in tetrahydroindacene), 2.14 (m, 2H, 3,3′-H intetrahydroindacene), 1.66-1.92 (m, 4H, two CH₂ groups in cyclohexyl),1.48 (m, 1H, 1-H in cyclohexyl), 1.17-1.34 (m, 6H, three CH₂ groups incyclohexyl), 1.00 (m, 2H, CH₂C₆H₁₁-c).

Preparation Example 112-(cyclohexylmethyl)-4-Bromo-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

To a mixture of 40.9 g (0.305 mol) of AlCl₃ in 180 ml of dichloromethane32.7 g (0.122 mol) of2-(cyclohexylmethyl)-3,5,6,7-tetrahydro-s-indacen-1(2H)one was added. Tothis mixture cooled to 0° C. 21.5 g (0.134 mol) of bromine was addeddropwise by vigorous stirring for 45 min at 0-5° C. The resultingmixture was stirred for 12 h at ambient temperature and then poured on1000 cm³ of ice. The organic layer was separated, and the aqueous layerwas extracted with 3×200 ml of dichloromethane. The combined organicextract was dried over Na₂SO₄ and then evaporated to dryness. Thisproduct was further used without an additional purification. Yield 39.5g (93%).

Anal. calc. for C₁₉H₂₃BrO: C, 65.71; H, 6.68. Found: C, 65.53; H, 6.58.

¹H NMR (CDCl₃): δ 7.39 (s, 1H, 8-H in tetrahydroindacene), 3.11 (dd,J=17.4 Hz, J=7.8 Hz, 1H, 3-H in tetrahydroindacene), 2.94 (m, 2H, 7-CH₂in tetrahydroindacene), 2.89 (m, 2H, 5-CH₂ in tetrahydroindacene), 2.66(m, 1H, 2-H in tetrahydroindacene), 2.55 (dd, J=17.4 Hz, J=3.8 Hz, 1H,3′-H in tetrahydroindacene), 2.05 (m, 2H, 6,6′-H in tetrahydroindacene),1.54-1.79 (m, 4H, two CH₂ groups in cyclohexyl), 1.38 (m, 1H, 1-H incyclohexyl), 0.72-1.23 (m, 8H, three CH₂ groups in cyclohexyl andCH₂C₆H₁₁-c).

Preparation Example 124-Bromo-6-(cyclohexylmethyl)-1,2,3,5-tetrahydro-s-indacene

To a solution of 39.5 g (0.114 mol) of4-bromo-2-(cyclohexylmethyl)-3,5,6,7-tetrahydro-s-indacen-1(2H)-one in170 ml of THF 15.2 g (0.398 mol) of NaBH₄ was added. Further on, 340 mlof methanol was added dropwise by vigorous stirring for 2 h. Theresulting mixture was stirred for 12 h at room temperature, evaporatedto a volume of ca. 300 ml, and then 100 ml of 3.0 M HCl was added. Theproduct was extracted with 3×200 ml of dichloromethane. The organicextract was dried over Na₂SO₄ and then evaporated to dryness. A solutionof the residue and 1.4 g of TsOH in 800 ml of toluene was refluxed for30 min with Dean-Stark head. The obtained solution was passed throughshort layer (50 mm) of silica gel 60 (40-63 um), the filtrate wasevaporated to dryness. This procedure gave 34.7 g (93%) of the titleproduct which was further used without an additional purification.

Anal. calc. for C₁₉H₂₃Br: C, 68.88; H, 7.00. Found: C, 68.69; H, 6.85.

¹H NMR (CDCl₃): δ 7.03 (s, 1H, 4-H in tetrahydroindacene), 6.45 (m, 1H,3-H in tetrahydroindacene), 3.23 (s, 2H, 1,1′-H in tetrahydroindacene),3.00 (m, 2H, 5-CH₂ in tetrahydroindacene), 2.95 (m, m, 2H, 7-CH₂ intetrahydroindacene), 2.34 (d, J=7.1 Hz, 2H, CH₂C₆H₁₁-c), 2.10 (m, 2H,6,6′-H in tetrahydroindacene), 1.62-1.76 (m, 4H, two CH₂ groups incyclohexyl), 1.54 (m, 1H, 1-H in cyclohexyl), 0.79-1.44 (m, 6H, threeCH₂ groups in cyclohexyl).

Preparation Example 134-(4-tert-Butylphenyl)-6-(cyclohexylmethyl)-1,2,3,5-tetrahydro-s-indacene

In argon atmosphere, a mixture of 34.6 g (105 mmol) of4-bromo-6-(cyclohexylmethyl)-1,2,3,5-tetrahydro-s-indacene, 22.4 g (126mmol) 4-tert-butylphenylboronic acid, 66.8 g (315 mmol) of K₃PO₄, 1.21 g(21 mmol) of Pd(dba)₂, 1.73 g (42 mmol) ofdicyclohexyl(2′,6′-dimethoxybiphenyl-2-yl)phosphine and 350 ml oftoluene was stirred for 12 h at 100° C. The resulting mixture was cooledto room temperature, and then 600 ml of water was added. The organiclayer was separated, and the aqueous layer was extracted with 3×100 mlof dichloromethane. The combined organic extract was dried over Na₂SO₄and then evaporated to dryness. The target product was isolated by flashchromatography on silica gel 60 (40-63 um; eluent: hexanes). Yield 24.0g (62%).

Anal. calc. for C₂₉H₃₆: C, 90.57; H, 9.43. Found: C, 90.44; H, 9.54.

¹H NMR (CDCl₃): δ 7.44-7.47 (m, 2H, 2,6-H in C₆H₄ ^(t)Bu), 7.33-7.37 (m,2H, 3,5-H in C₆H₄ ^(t)Bu), 7.15 (s, 1H, 4-H in tetrahydroindacene), 6.49(m, 1H, 3-H in tetrahydroindacene), 3.21 (s, 2H, 1,1′-H intetrahydroindacene), 2.99 (m, 2H, 5-CH₂ in tetrahydroindacene), 2.82 (m,2H, 7-CH₂ in tetrahydroindacene), 2.31 (d, J=7.1 Hz, 2H, CH₂C₆H₁₁-c),2.05 (m, 2H, 6,6′-H in tetrahydroindacene), 1.60-1.75 (m, 4H, two CH₂groups in cyclohexyl), 1.49 (m, 1H, 1-H in cyclohexyl), 1.40 (s, 9H,^(t)Bu), 0.75-1.36 (m, 6H, three CH₂ groups in cyclohexyl).

Preparation Example 14Bis[2-(cyclohexylmethyl)-4-(4-tert-butylphenyl)-1,5,6,7-tetrahydro-s-indacen-1-yl](dimethyl)silane

To a solution of 20.8 g (54.1 mmol) of4-(4-tert-butylphenyl)-6-(cyclohexylmethyl)-1,2,3,5-tetrahydro-s-indacenein 600 ml of toluene 21.7 ml (54.2 mmol) of 2.5 M ^(n)BuLi in hexaneswas added dropwise at 20° C. Then, 30 ml of THF was added, and theresulting mixture was stirred for 1 h at 70° C. The resulting mixturewas cooled to 0° C., and 3.30 ml (3.49 g, 27.1 mmol) ofdichlorodimethylsilane was added. This mixture was stirred for 12 h atroom temperature, then 5 ml of water was added, and organic solventswere evaporated using Rotavapor. The product was extracted from theresidue by 3×100 ml of dichloromethane. The organic extract was driedover Na₂SO₄ and then evaporated to dryness. The product was isolated byflash chromatography on silica gel 60 (40-63 um, eluent: hexanes andthen hexanes-dichloromethane, 10:1, vol.). Yield 15.2 g (68%).

Anal. calc. for C₆₀H₇₆Si: C, 87.32; H, 9.28. Found: C, 87.23; H, 9.42.

¹H NMR (CDCl₃): δ 7.45-7.49 (m, 8H, 2,6-H in C₆H₄ ^(t)Bu of rac- andmeso-), 7.35-7.41 (m, 8H, 3,5-H in C₆H₄ ^(t)Bu of rac- and meso-), 7.26(s, 2H, 4-H in tetrahydroindacene of meso-), 7.22 (s, 2H, 4-H intetrahydroindacene of rac-), 6.59 (br.s, 4H, 3-H in tetrahydroindacenerac- and meso-), 3.76 (s, 2H, 1-H in tetrahydroindacene of meso-), 3.74(s, 2H, 1-H in tetrahydroindacene of rac-), 2.82-3.01 (m, 16H, 5,7-CH₂in tetrahydroindacene of rac- and meso-), 2.32-2.48 (m, 8H, CH₂C₆H₁₁-c),2.06 (m, 8H, 6,6′-H in tetrahydroindacene of rac- and meso-), 1.57-1.75(m, 16H, two CH₂ groups in cyclohexyl of rac- and meso-), 1.42 (s, 18H,^(t)Bu of meso-), 1.41 (s, 18H, ^(t)Bu of rac-), 0.77-1.32 (m, 28H,three CH₂ groups and 1-H in cyclohexyl of rac- and meso-), −0.14 (s, 3H,SiMeMe′ of meso-), −0.18 (s, 3H, SiMe₂ of rac-), −0.30 (s, 3H, SiMeMe′of meso-).

Preparation Example 15rac-1,1′-dimethylsilylene-bis[2-(cyclohexylmethyl)-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]zirconiumdichloride

To a solution of 6.60 g (8.0 mmol) ofbis[4-(4-tert-butylphenyl)-2-(cyclohexylmethyl)-1,5,6,7-tetrahydro-s-indacen-1-yl](dimethyl)silanein 150 ml of diethyl ether 6.40 ml (16.0 mmol) of 2.5 M ^(n)BuLi inhexanes was added dropwise at 20° C. This mixture was stirred for 12 hat ambient temperature, then cooled to −78° C., and 3.02 g (8.0 mmol) ofZrCl₄(THF)₂ was added. The resulting mixture was stirred for 12 h atroom temperature and then evaporated to dryness. The residue was driedin vacuum, and then 60 ml of toluene was added. The obtained suspensionwas stirred for 4 h at 60° C., then this hot mixture was filteredthrough Celite 503. The Celite layer was additionally washed by 20 ml oftoluene. The combined filtrate was evaporated to a volume of ca. 40 ml.The formed suspension was heated to reflux in order to dissolve theprecipitate. Crystals precipitated from this solution at roomtemperature were collected, washed by 3 ml of cold toluene, 5 ml of coldhexanes and then dried in vacuum. This procedure gave 0.91 g (11%) ofpure rac-complex. The mother liquid was evaporated to a volume of ca. 20ml. Again, this mixture was heated to reflux. Crystals precipitated atroom temperature were collected, washed by 3 ml of cold toluene, 5 ml ofcold hexanes and then dried in vacuum. This procedure gave 0.58 g of aca. 10 to 1 mixture of rac- and meso-complexes. Crystallization of thismixture from hexanes-toluene (7:1, vol.) gave additional 0.45 g (5%) ofpure rac-complex.

Anal. calc. for C₆₀H₇₄Cl₂SiZr: C, 73.13; H, 7.57. Found: C, 73.28; H,7.66.

¹H NMR (CD₂Cl₂): δ 7.46 (m, 8H, C₆H₄ ^(t)Bu), 7.44 (s, 2H, 8-H intetrahydroindacene), 6.64 (s, 2H, 3-H in tetrahydroindacene), 2.76-3.04(m, 8H, 5,5′,7,7′-H in tetrahydroindacene), 2.65 (dd, J=13.9 Hz, J=6.8Hz, 2H, CHH′C₆H₁₁-c), 2.07 (dd, J=13.9 Hz, J=7.6 Hz, 2H, CHH′C₆H₁₁-c),1.98 (m, 4H, 6,6′-H in tetrahydroindacene), 1.60 (m, 8H, two CH₂ groupsin cyclohexyl), 1.47 (m, 2H, 1-H in cyclohexyl), 1.35 (s, 18H, ^(t)Bu),1.30 (s, 6H, SiMe₂), 0.76-1.22 (m, 12H, three CH₂ groups in cyclohexyl).

Catalyst Preparation

MAO was purchased from Albemarle and used as a 30 wt-% solution intoluene. Perfluoroalkylethyl acrylate esters (CAS number 65605-70-1)were purchased from the Cytonix Corporation, dried and degassed prior touse. Hexadecafluoro-1,3-dimethylcyclohexane was dried and degassed priorto use.

Inventive Metallocene 1:rac-1,1′-dimethylsilylene-bis[2-isobutyl-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]zirconiumdichloride

Inventive Metallocene 2:rac-1,1′-dimethylsilylene-bis[2-(cyclohexylmethyl)-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]zirconiumdichloride

Comparative Metallocene 1

rac-1,1′-dimethylsilylene-bis[2-methyl-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]}zirconiumdichloride) was prepared as described in WO2006/097497A1. Its ¹H NMRspectrum corresponds to that reported in the mentioned patentapplication.

Example 1 (E1)

The catalyst was prepared according to the procedure described in theExample 5 of WO 2003/051934 with hexadecafluoro-1,3-dimethylcyclohexaneas the immiscible solvent, a mixture of perfluoroalkylethyl acrylateesters having different perfluoroalkyl chain lengths as the surfactantprecursor andrac-1,1′-dimethylsilylene-bis[2-isobutyl-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]zirconiumdichloride as the metallocene.

The detailed catalyst preparation was performed as follows:

Inside a glovebox, 80 μL of a commercial mixture of dry and degassedperfluoroalkylethyl acrylate esters were mixed with 2 mL of MAO in aseptum bottle and left to react overnight (surfactant solution). Thefollowing day, 68.80 mg of the metallocene (0.076 mmol, 1 equivalent)were dissolved in 4 mL of the MAO solution in another septum bottle andleft to stir inside the glovebox (catalyst solution).

After 60 minutes, the 4 mL of the catalyst solution and 1 mL of thesurfactant solution were successively added into a 50 mL emulsificationglass reactor containing 40 mL of hexadecafluoro-1,3-dimethylcyclohexaneat −10° C. and equipped with an overhead stirrer (stirring speed=600rpm). A red-orange emulsion formed immediately (measured emulsionstability=15 seconds) and was stirred during 15 minutes at 0° C./600rpm. The emulsion was then transferred via a 2/4 Teflon tube to 100 mLof hot hexadecafluoro-1,3-dimethylcyclohexane at 90° C., and stirred at600 rpm until the transfer was completed. The stirring speed was reducedto 300 rpm and the oil bath was removed. Stirring was continued at roomtemperature for 15 more minutes. When the stirrer was switched off, thecatalyst was left to settle up on top of the continuous phase which wassiphoned off after 45 minutes. The remaining red solid catalyst wasdried during 2 hours at 50° C. over an argon flow.

Example 2 (E2)

The catalyst was synthesised following the above described protocols ofExample 1 with 0.076 mmol (1 equivalent, 74.90 mg) ofrac-1,1′-dimethylsilylene-bis[2-(cyclohexylmethyl)-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]zirconiumdichloride as the metallocene.

Comparative example 1 (CE1)

The catalyst was synthesised following the above described protocols ofExample 1 with 0.076 mmol (1 equivalent, 61.50 mg) ofrac-1,1′-dimethylsilylene-bis[2-methyl-4-(4-tert-butylphenyl)-5,6,7-trihydro-s-indacen-1-yl]}zirconiumdichloride as the metallocene.

TABLE 1 Catalyst syntheses summary Code Al(wt-%) Zr(wt-%) Al/Zr (molar)E1 26.10 0.33 267 E2 21.40 0.23 314 CE1 25.20 0.32 267

Polymerisation of Propylene and Ethylene to Form Random Copolymers:

The polymerisation experiments were performed in a 5 L reactor, 200 μlof triethylaluminum was fed as a scavenger in 5 mL of dry and degassedpentane. The desired amount of hydrogen was then loaded (measured inmmol) and 1100 g of liquid propylene was fed into the reactor followedby the desired amount of ethylene (fed into the gas phase). Thetemperature was set to 30° C. The desired amount of catalyst in 5 mL ofPFC was flushed into the reactor with a nitrogen overpressure. Thetemperature was then raised to 70° C. over a period of 15 minutes. Thepolymerisation was stopped after 30 minutes by venting the reactor andflushing with nitrogen before the polymer is collected. The catalysts ofthe invention E1 and E2 were tested (Tables 2 and 3) and compared tocomparative catalyst 1 (Table 4).

TABLE 2 Random C3/C2 copolymerisation data. Metal activity MFR₂ MFR₂₁Cata- H₂ C₂ feed Activity (kg/g (g/10 (g/10 Exp lyst (mmol) (g)(kg/gcat/h) Zr/h) min) min) 1 E1 6.0 0 109 33061 2.6 2 E1 6.0 7 13841818 1.9 3 E1 6.0 20 147 44545 0.9 4 E1 6.0 40 112 33939 0.4 5 E1 6.050 90 27273 0.3 6 E1 1.0 0 33 10091 ≈0.1 6.4 7 E1 1.0 20 61 18485 3.8 8E2 6.0 0 106 17696 3.3 9 E2 6.0 20 154 66957 0.3 10 E2 6.0 40 141 613040.3 11 E2 6.0 50 104 45217 0.3

TABLE 3 Random C3/C2 copolymers analyses. C2 content - MFR₂ MFR₂₁ ¹³C(g/10 (g/10 M_(w) exp. M_(n) exp. T_(m) T_(c) XS NMR Exp. Catalyst min)min) (kg/mol) (kg/mol) MWD (° C.) (° C.) (%) (wt-%) 1 E1 2.6 329 148 2.2155.6 112.0 0.2 0.0 2 E1 1.9 364 163 2.2 150.7 108.3 0.1 1.1 3 E1 0.9433 197 2.2 141.1 101.6 <0.1 1.7 4 E1 0.4 479 209 2.3 127.6 88.5 0.1 3.75 E1 0.3 526 204 2.6 120.3 81.7 0.7 4.1 6 E1 6.4 723 308 2.4 155.9 111.60.3 0.0 7 E1 3.8 694 200 3.5 141.0 99.5 — 2.2 8 E2 3.3 300 144 2.1 156.2114.8 0.1 0.0 9 E2 0.9 418 190 2.2 141.1 100.4 0.2 2.0 10 E2 0.3 510 2092.4 127.8 89.9 0.2 3.8 11 E2 0.3 548 220 2.5 119.8 75.9 0.3 4.6

TABLE 4 Comparison with CE1 vs E1 CE1 CE1 CE1 Inv E1 Inv E1 Inv E1 C2feed H2 feed Activity MFR2 C2 content Activity MFR2 C2 content (g)(mmol) (kg/gcat/h) (g/10 min) (wt-%) (kg/gcat/h) (g/10 min) (wt-%) 0 692 2 0.0 109 2.6 0.0 20 6 128 0.4 2.1 147 0.9 1.7 50 6 49 0.1 4.6 90 0.34.1 Comparison with CE1 vs E2 CE1 CE1 CE1 Inv E2 Inv E2 Inv E2 C2 feedH2 feed Activity MFR2 C2 content Activity MFR2 C2 content (g) (mmol)(kg/gcat/h) (g/10 min) (wt-%) (kg/gcat/h (g/10 min) (wt-%) 0 6 92 2 0.0106 3.3 0.0 20 6 128 0.4 2.1 154 0.3 2.0 50 6 49 0.1 4.6 104 0.3 4.6

1. A process for the preparation of a random propylene copolymercomprising polymerising propylene and at least one C₂₋₁₀ alpha olefin inthe presence of a catalyst; wherein said catalyst comprises: (i) acomplex of formula (I):

wherein M is zirconium or hafnium; each X is a sigma ligand; L is adivalent bridge selected from —R′₂C—, —R′₂C—CR′₂—, —R′₂Si—,—R′₂Si—SiR'₂—, —R′₂Ge—, wherein each R′ is independently a hydrogenatom, C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl,C7-C20-arylalkyl or C7-C20-alkylaryl; each R¹ is a C4-C20 hydrocarbylradical branched at the β-atom to the cyclopentadienyl ring, optionallycontaining one or more heteroatoms belonging to groups 14-16, or is aC3-C20 hydrocarbyl radical branched at the β-atom to thecyclopentadienyl ring where the β-atom is an Si-atom; n is 0-3; each R¹⁸is the same or different and may be a C1-C20 hydrocarbyl radicaloptionally containing one or more heteroatoms belonging to groups 14-16;each R⁴ is a hydrogen atom or a C₁₋₆-hydrocarbyl radical; each W is a 5or 6 membered aryl or heteroaryl ring wherein each atom of said ring isoptionally substituted with an R⁵ group; each R⁵ is the same ordifferent and is a C1-C20 hydrocarbyl radical optionally containing oneor more heteroatoms belonging to groups 14-16; and optionally twoadjacent R⁵ groups taken together can form a further mono or multicyclicring condensed to W optionally substituted by one or two groups R⁵; and(ii) a cocatalyst comprising an organometallic compound of a Group 13metal.
 2. A process as claimed in claim 1 wherein the catalyst isprepared by a process comprising (I) forming a liquid/liquid emulsionsystem, said liquid/liquid emulsion system comprising a solution of thecatalyst components (i) and (ii) dispersed in a solvent so as to formdispersed droplets; and (II) solidifying said dispersed droplets to formsolid particles.
 3. A process as claimed in claim 1, wherein thecatalyst further comprises an inert carrier.
 4. A process as claimed inclaim 1, wherein in said complex of formula (I), L is —SiR⁶ ₂—, whereineach R⁶ is independently C1-C20-alkyl, C6-C20-aryl ortri(C1-C20-alkyl)silyl-residue or ethylene bridge.
 5. A process asclaimed in claim 1, wherein in said complex of formula (I) R¹ is thegroup —CH₂—R^(1′) and R^(1′) represents a C3-19 hydrocarbyl groupoptionally containing one or more heteroatoms belonging to groups 14-16,a C2-19 hydrocarbyl group where the β-atom to the cyclopentadienyl ringis an Si-atom, so as to provide a branch β to the cyclopentadienyl ring,a C₃₋₇-cycloalkyl group optionally substituted by C₁₋₆-alkyl, aC₆₋₁₀-aryl group, or an C₃₋₈-alkyl group such that the position β tocyclopentadienyl is branched.
 6. A process as claimed in claim 1,wherein in said complex of formula (I) n is
 0. 7. A process as claimedin claim 1, wherein in said complex of formula (I) R⁴ is a hydrogen atomor methyl, ethyl, propyl or isopropyl group.
 8. A process as claimed inclaim 1, wherein in said complex of formula (I) W is an optionallysubstituted phenyl group, or a 5 or 6 membered heteroaryl group selectedfrom furanyl, thiophenyl, pyrrolyl, triazolyl, and pyridinyl.
 9. Aprocess as claimed in claim 1, wherein in said complex of formula (I) R⁵is a linear or branched, cyclic or acyclic, C1-C10-alkyl group or twoadjacent R⁵ groups taken together form a further mono or multicyclicaromatic ring condensed to W.
 10. A process as claimed in claim 1,wherein said catalyst comprises a complex of formula (II):

wherein M is Zr or Hf; each R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) whereinR³ is a C₁₋₆-alkyl group or together two R³ groups form aC₃₋₇-cycloalkyl ring wherein said ring is optionally substituted by aC₁₋₆ alkyl group and q can be 1 or 0; L is ethylene or SiR⁶ ₂; R⁶ isC1-10 alkyl, C₆₋₁₀-aryl, C₇₋₁₂-alkylaryl, or C₇₋₁₂-arylalkyl; each X isa hydrogen atom, —OR, a halogen atom, or an R group; R is C₁₋₁₀ alkyleach R⁴ is H or C₁₋₃-alkyl; n is 0 to 3; each W′ is aryl, pyridyl,thiophenyl, or furyl optionally substituted by up to 2 groups R⁵; eachR⁵ is C₁₋₁₀-alkyl or two adjacent R⁵ groups taken together form a phenylring fused to W′ or two adjacent R⁵ groups taken together form the atomsnecessary to form a carbazolyl group with the W′ group; and each R¹⁸ isC₁₋₆-alkyl; and wherein the two ligands forming the complex areidentical.
 11. A process as claimed in claim 1, wherein said catalystcomprises a complex of formula (III)

wherein M is Zr or Hf; each R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) whereinR³ is a C₁₋₆-alkyl group or together two R³ groups form aC₃₋₇-cycloalkyl ring wherein said ring is optionally substituted by aC₁₋₆ alkyl group and q can be 1 or 0; L is SiR⁶ ₂; R⁶ is C1-10 alkyl,C₆₋₁₀-aryl, C₇₋₁₂-alkylaryl, or C₇₋₁₂-arylalkyl; each X is a hydrogenatom, OR, a halogen atom, or an R group; R is C₁₋₁₀ alkyl each R⁴ is Hor C₁₋₃-alkyl; n is 0 to 2; p is 0 to 2; each R⁵ is C₁₋₁₀-alkyl and eachR¹⁸ is C₁₋₆-alkyl; and wherein the two ligands forming the complex areidentical.
 12. A process as claimed in claim 1, wherein said catalystcomprises a complex of formula (IV)

in which: M is Zr; each R¹ is CH₂-Ph, CH₂—C(R³)_(3-q)(H)_(q) wherein R³is a C₁₋₆-alkyl group or together two R³ groups form a C₃₋₇-cycloalkylring wherein said ring is optionally substituted by a C₁₋₆ alkyl groupand q can be 1 or 0; L is SiR⁶ ₂; R⁶ is C₁₋₆ alkyl; each X is a halogenatom, or methyl; each R⁴ is H or methyl p is 0 or 1; and R⁵ is C1-6alkyl; and wherein the two ligands forming the complex are identical.13. A process as claimed in claim 1, wherein said catalyst comprises acomplex of formula (V)

wherein p is 0 or 1; L is SiR⁶ ₂; R⁵ is a group C(R²)₃; R¹ is CH₂-Ph,CH₂—C(R³)_(3-q)(H)_(q) wherein R³ is a C₁₋₆-alkyl group or together twoR³ groups form a C₃₋₇-cycloalkyl ring wherein said ring is optionallysubstituted by a C₁₋₆ alkyl group and q can be 1 or 0; R² is aC1-6-alkyl group; R³ is a C1-6-alkyl group or together two R³ groupsform a C₃₋₇-cycloalkyl ring; q is 0 or 1; each X is a halogen atom,methoxy, or methyl; and M is Zr; and wherein the two ligands forming thecomplex are identical.
 14. A random propylene copolymer prepared by theprocess of claim
 1. 15. A random propylene ethylene copolymer having upto 7 wt % of ethylene having a Mw of at least 300,000 and a xylenesoluble fraction of less than 0.75 wt %.